1---
2NTP 4.2.8p8 (Harlan Stenn <stenn@ntp.org>, 2016/06/02)
3
4Focus: Security, Bug fixes, enhancements.
5
6Severity: HIGH
7
8In addition to bug fixes and enhancements, this release fixes the
9following 1 high- and 4 low-severity vulnerabilities:
10
11* CRYPTO_NAK crash
12 Date Resolved: 02 June 2016; Dev (4.3.93) 02 June 2016
13 References: Sec 3046 / CVE-2016-4957 / VU#321640
14 Affects: ntp-4.2.8p7, and ntp-4.3.92.
15 CVSS2: HIGH 7.8 (AV:N/AC:L/Au:N/C:N/I:N/A:C)
16 CVSS3: HIGH 7.5 CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
17 Summary: The fix for Sec 3007 in ntp-4.2.8p7 contained a bug that
18 could cause ntpd to crash.
19 Mitigation:
20 Implement BCP-38.
21 Upgrade to 4.2.8p8, or later, from the NTP Project Download Page
22 or the NTP Public Services Project Download Page
23 If you cannot upgrade from 4.2.8p7, the only other alternatives
24 are to patch your code or filter CRYPTO_NAK packets.
25 Properly monitor your ntpd instances, and auto-restart ntpd
26 (without -g) if it stops running.
27 Credit: This weakness was discovered by Nicolas Edet of Cisco.
28
29* Bad authentication demobilizes ephemeral associations
30 Date Resolved: 02 June 2016; Dev (4.3.93) 02 June 2016
31 References: Sec 3045 / CVE-2016-4953 / VU#321640
32 Affects: ntp-4, up to but not including ntp-4.2.8p8, and
33 ntp-4.3.0 up to, but not including ntp-4.3.93.
34 CVSS2: LOW 2.6 (AV:N/AC:H/Au:N/C:N/I:N/A:P)
35 CVSS3: LOW 3.7 CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L
36 Summary: An attacker who knows the origin timestamp and can send a
37 spoofed packet containing a CRYPTO-NAK to an ephemeral peer
38 target before any other response is sent can demobilize that
39 association.
40 Mitigation:
41 Implement BCP-38.
42 Upgrade to 4.2.8p8, or later, from the NTP Project Download Page
43 or the NTP Public Services Project Download Page
44 Properly monitor your ntpd instances.
45 Credit: This weakness was discovered by Miroslav Lichvar of Red Hat.
46
47* Processing spoofed server packets
48 Date Resolved: 02 June 2016; Dev (4.3.93) 02 June 2016
49 References: Sec 3044 / CVE-2016-4954 / VU#321640
50 Affects: ntp-4, up to but not including ntp-4.2.8p8, and
51 ntp-4.3.0 up to, but not including ntp-4.3.93.
52 CVSS2: LOW 2.6 (AV:N/AC:H/Au:N/C:N/I:N/A:P)
53 CVSS3: LOW 3.7 CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L
54 Summary: An attacker who is able to spoof packets with correct origin
55 timestamps from enough servers before the expected response
56 packets arrive at the target machine can affect some peer
57 variables and, for example, cause a false leap indication to be set.
58 Mitigation:
59 Implement BCP-38.
60 Upgrade to 4.2.8p8, or later, from the NTP Project Download Page
61 or the NTP Public Services Project Download Page
62 Properly monitor your ntpd instances.
63 Credit: This weakness was discovered by Jakub Prokes of Red Hat.
64
65* Autokey association reset
66 Date Resolved: 02 June 2016; Dev (4.3.93) 02 June 2016
67 References: Sec 3043 / CVE-2016-4955 / VU#321640
68 Affects: ntp-4, up to but not including ntp-4.2.8p8, and
69 ntp-4.3.0 up to, but not including ntp-4.3.93.
70 CVSS2: LOW 2.6 (AV:N/AC:H/Au:N/C:N/I:N/A:P)
71 CVSS3: LOW 3.7 CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L
72 Summary: An attacker who is able to spoof a packet with a correct
73 origin timestamp before the expected response packet arrives at
74 the target machine can send a CRYPTO_NAK or a bad MAC and cause
75 the association's peer variables to be cleared. If this can be
76 done often enough, it will prevent that association from working.
77 Mitigation:
78 Implement BCP-38.
79 Upgrade to 4.2.8p8, or later, from the NTP Project Download Page
80 or the NTP Public Services Project Download Page
81 Properly monitor your ntpd instances.
82 Credit: This weakness was discovered by Miroslav Lichvar of Red Hat.
83
84* Broadcast interleave
85 Date Resolved: 02 June 2016; Dev (4.3.93) 02 June 2016
86 References: Sec 3042 / CVE-2016-4956 / VU#321640
87 Affects: ntp-4, up to but not including ntp-4.2.8p8, and
88 ntp-4.3.0 up to, but not including ntp-4.3.93.
89 CVSS2: LOW 2.6 (AV:N/AC:H/Au:N/C:N/I:N/A:P)
90 CVSS3: LOW 3.7 CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L
91 Summary: The fix for NtpBug2978 does not cover broadcast associations,
92 so broadcast clients can be triggered to flip into interleave mode.
93 Mitigation:
94 Implement BCP-38.
95 Upgrade to 4.2.8p8, or later, from the NTP Project Download Page
96 or the NTP Public Services Project Download Page
97 Properly monitor your ntpd instances.
98 Credit: This weakness was discovered by Miroslav Lichvar of Red Hat.
99
100Other fixes:
101* [Bug 3038] NTP fails to build in VS2015. perlinger@ntp.org
102 - provide build environment
103 - 'wint_t' and 'struct timespec' defined by VS2015
104 - fixed print()/scanf() format issues
105* [Bug 3052] Add a .gitignore file. Edmund Wong.
106* [Bug 3054] miscopt.html documents the allan intercept in seconds. SWhite.
107* [Bug 3058] fetch_timestamp() mishandles 64-bit alignment. Brian Utterback,
108 JPerlinger, HStenn.
109* Fix typo in ntp-wait and plot_summary. HStenn.
110* Make sure we have an "author" file for git imports. HStenn.
111* Update the sntp problem tests for MacOS. HStenn.
112
113---
114NTP 4.2.8p7 (Harlan Stenn <stenn@ntp.org>, 2016/04/26)
115
116Focus: Security, Bug fixes, enhancements.
117
118Severity: MEDIUM
119
120When building NTP from source, there is a new configure option
121available, --enable-dynamic-interleave. More information on this below.
122
123Also note that ntp-4.2.8p7 logs more "unexpected events" than previous
124versions of ntp. These events have almost certainly happened in the
125past, it's just that they were silently counted and not logged. With
126the increasing awareness around security, we feel it's better to clearly
127log these events to help detect abusive behavior. This increased
128logging can also help detect other problems, too.
129
130In addition to bug fixes and enhancements, this release fixes the
131following 9 low- and medium-severity vulnerabilities:
132
133* Improve NTP security against buffer comparison timing attacks,
134 AKA: authdecrypt-timing
135 Date Resolved: Stable (4.2.8p7) 26 Apr 2016; Dev (4.3.92) 26 Apr 2016
136 References: Sec 2879 / CVE-2016-1550
137 Affects: All ntp-4 releases up to, but not including 4.2.8p7, and
138 4.3.0 up to, but not including 4.3.92
139 CVSSv2: LOW 2.6 - (AV:L/AC:H/Au:N/C:P/I:P/A:N)
140 CVSSv3: MED 4.0 - CVSS:3.0/AV:L/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N
141 Summary: Packet authentication tests have been performed using
142 memcmp() or possibly bcmp(), and it is potentially possible
143 for a local or perhaps LAN-based attacker to send a packet with
144 an authentication payload and indirectly observe how much of
145 the digest has matched.
146 Mitigation:
147 Upgrade to 4.2.8p7, or later, from the NTP Project Download Page
148 or the NTP Public Services Project Download Page.
149 Properly monitor your ntpd instances.
150 Credit: This weakness was discovered independently by Loganaden
151 Velvindron, and Matthew Van Gundy and Stephen Gray of Cisco ASIG.
152
153* Zero origin timestamp bypass: Additional KoD checks.
154 References: Sec 2945 / Sec 2901 / CVE-2015-8138
155 Affects: All ntp-4 releases up to, but not including 4.2.8p7,
156 Summary: Improvements to the fixes incorporated in t 4.2.8p6 and 4.3.92.
157
158* peer associations were broken by the fix for NtpBug2899
159 Date Resolved: Stable (4.2.8p7) 26 Apr 2016; Dev (4.3.92) 26 Apr 2016
160 References: Sec 2952 / CVE-2015-7704
161 Affects: All ntp-4 releases up to, but not including 4.2.8p7, and
162 4.3.0 up to, but not including 4.3.92
163 CVSSv2: MED 4.3 - (AV:N/AC:M/Au:N/C:N/I:N/A:P)
164 Summary: The fix for NtpBug2952 in ntp-4.2.8p5 to address broken peer
165 associations did not address all of the issues.
166 Mitigation:
167 Implement BCP-38.
168 Upgrade to 4.2.8p7, or later, from the NTP Project Download Page
169 or the NTP Public Services Project Download Page
170 If you can't upgrade, use "server" associations instead of
171 "peer" associations.
172 Monitor your ntpd instances.
173 Credit: This problem was discovered by Michael Tatarinov.
174
175* Validate crypto-NAKs, AKA: CRYPTO-NAK DoS
176 Date Resolved: Stable (4.2.8p7) 26 Apr 2016; Dev (4.3.92) 26 Apr 2016
177 References: Sec 3007 / CVE-2016-1547 / VU#718152
178 Affects: All ntp-4 releases up to, but not including 4.2.8p7, and
179 4.3.0 up to, but not including 4.3.92
180 CVSS2: MED 4.3 - (AV:N/AC:M/Au:N/C:N/I:N/A:P)
181 CVSS3: MED 3.7 - CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L
182 Summary: For ntp-4 versions up to but not including ntp-4.2.8p7, an
183 off-path attacker can cause a preemptable client association to
184 be demobilized by sending a crypto NAK packet to a victim client
185 with a spoofed source address of an existing associated peer.
186 This is true even if authentication is enabled.
187
188 Furthermore, if the attacker keeps sending crypto NAK packets,
189 for example one every second, the victim never has a chance to
190 reestablish the association and synchronize time with that
191 legitimate server.
192
193 For ntp-4.2.8 thru ntp-4.2.8p6 there is less risk because more
194 stringent checks are performed on incoming packets, but there
195 are still ways to exploit this vulnerability in versions before
196 ntp-4.2.8p7.
197 Mitigation:
198 Implement BCP-38.
199 Upgrade to 4.2.8p7, or later, from the NTP Project Download Page
200 or the NTP Public Services Project Download Page
201 Properly monitor your =ntpd= instances
202 Credit: This weakness was discovered by Stephen Gray and
203 Matthew Van Gundy of Cisco ASIG.
204
205* ctl_getitem() return value not always checked
206 Date Resolved: Stable (4.2.8p7) 26 Apr 2016; Dev (4.3.92) 26 Apr 2016
207 References: Sec 3008 / CVE-2016-2519
208 Affects: All ntp-4 releases up to, but not including 4.2.8p7, and
209 4.3.0 up to, but not including 4.3.92
210 CVSSv2: MED 4.9 - (AV:N/AC:H/Au:S/C:N/I:N/A:C)
211 CVSSv3: MED 4.2 - CVSS:3.0/AV:N/AC:H/PR:H/UI:R/S:U/C:N/I:N/A:H
212 Summary: ntpq and ntpdc can be used to store and retrieve information
213 in ntpd. It is possible to store a data value that is larger
214 than the size of the buffer that the ctl_getitem() function of
215 ntpd uses to report the return value. If the length of the
216 requested data value returned by ctl_getitem() is too large,
217 the value NULL is returned instead. There are 2 cases where the
218 return value from ctl_getitem() was not directly checked to make
219 sure it's not NULL, but there are subsequent INSIST() checks
220 that make sure the return value is not NULL. There are no data
221 values ordinarily stored in ntpd that would exceed this buffer
222 length. But if one has permission to store values and one stores
223 a value that is "too large", then ntpd will abort if an attempt
224 is made to read that oversized value.
225 Mitigation:
226 Implement BCP-38.
227 Upgrade to 4.2.8p7, or later, from the NTP Project Download Page
228 or the NTP Public Services Project Download Page
229 Properly monitor your ntpd instances.
230 Credit: This weakness was discovered by Yihan Lian of the Cloud
231 Security Team, Qihoo 360.
232
233* Crafted addpeer with hmode > 7 causes array wraparound with MATCH_ASSOC
234 Date Resolved: Stable (4.2.8p7) 26 Apr 2016; Dev (4.3.92) 26 Apr 2016
235 References: Sec 3009 / CVE-2016-2518 / VU#718152
236 Affects: All ntp-4 releases up to, but not including 4.2.8p7, and
237 4.3.0 up to, but not including 4.3.92
238 CVSS2: LOW 2.1 - (AV:N/AC:H/Au:S/C:N/I:N/A:P)
239 CVSS3: LOW 2.0 - CVSS:3.0/AV:N/AC:H/PR:H/UI:R/S:U/C:N/I:N/A:L
240 Summary: Using a crafted packet to create a peer association with
241 hmode > 7 causes the MATCH_ASSOC() lookup to make an
242 out-of-bounds reference.
243 Mitigation:
244 Implement BCP-38.
245 Upgrade to 4.2.8p7, or later, from the NTP Project Download Page
246 or the NTP Public Services Project Download Page
247 Properly monitor your ntpd instances
248 Credit: This weakness was discovered by Yihan Lian of the Cloud
249 Security Team, Qihoo 360.
250
251* remote configuration trustedkey/requestkey/controlkey values are not
252 properly validated
253 Date Resolved: Stable (4.2.8p7) 26 Apr 2016; Dev (4.3.92) 26 Apr 2016
254 References: Sec 3010 / CVE-2016-2517 / VU#718152
255 Affects: All ntp-4 releases up to, but not including 4.2.8p7, and
256 4.3.0 up to, but not including 4.3.92
257 CVSS2: MED 4.9 - (AV:N/AC:H/Au:S/C:N/I:N/A:C)
258 CVSS3: MED 4.2 - CVSS:3.0/AV:N/AC:H/PR:H/UI:R/S:U/C:N/I:N/A:H
259 Summary: If ntpd was expressly configured to allow for remote
260 configuration, a malicious user who knows the controlkey for
261 ntpq or the requestkey for ntpdc (if mode7 is expressly enabled)
262 can create a session with ntpd and then send a crafted packet to
263 ntpd that will change the value of the trustedkey, controlkey,
264 or requestkey to a value that will prevent any subsequent
265 authentication with ntpd until ntpd is restarted.
266 Mitigation:
267 Implement BCP-38.
268 Upgrade to 4.2.8p7, or later, from the NTP Project Download Page
269 or the NTP Public Services Project Download Page
270 Properly monitor your =ntpd= instances
271 Credit: This weakness was discovered by Yihan Lian of the Cloud
272 Security Team, Qihoo 360.
273
274* Duplicate IPs on unconfig directives will cause an assertion botch in ntpd
275 Date Resolved: Stable (4.2.8p7) 26 Apr 2016; Dev (4.3.92) 26 Apr 2016
276 References: Sec 3011 / CVE-2016-2516 / VU#718152
277 Affects: All ntp-4 releases up to, but not including 4.2.8p7, and
278 4.3.0 up to, but not including 4.3.92
279 CVSS2: MED 6.3 - (AV:N/AC:M/Au:S/C:N/I:N/A:C)
280 CVSS3: MED 4.2 - CVSS:3.0/AV:N/AC:H/PR:H/UI:R/S:U/C:N/I:N/A:H
281 Summary: If ntpd was expressly configured to allow for remote
282 configuration, a malicious user who knows the controlkey for
283 ntpq or the requestkey for ntpdc (if mode7 is expressly enabled)
284 can create a session with ntpd and if an existing association is
285 unconfigured using the same IP twice on the unconfig directive
286 line, ntpd will abort.
287 Mitigation:
288 Implement BCP-38.
289 Upgrade to 4.2.8p7, or later, from the NTP Project Download Page
290 or the NTP Public Services Project Download Page
291 Properly monitor your ntpd instances
292 Credit: This weakness was discovered by Yihan Lian of the Cloud
293 Security Team, Qihoo 360.
294
295* Refclock impersonation vulnerability
296 Date Resolved: Stable (4.2.8p7) 26 Apr 2016; Dev (4.3.92) 26 Apr 2016
297 References: Sec 3020 / CVE-2016-1551
298 Affects: On a very limited number of OSes, all NTP releases up to but
299 not including 4.2.8p7, and 4.3.0 up to but not including 4.3.92.
300 By "very limited number of OSes" we mean no general-purpose OSes
301 have yet been identified that have this vulnerability.
302 CVSSv2: LOW 2.6 - (AV:N/AC:H/Au:N/C:N/I:P/A:N)
303 CVSSv3: LOW 3.7 - CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
304 Summary: While most OSes implement martian packet filtering in their
305 network stack, at least regarding 127.0.0.0/8, some will allow
306 packets claiming to be from 127.0.0.0/8 that arrive over a
307 physical network. On these OSes, if ntpd is configured to use a
308 reference clock an attacker can inject packets over the network
309 that look like they are coming from that reference clock.
310 Mitigation:
311 Implement martian packet filtering and BCP-38.
312 Configure ntpd to use an adequate number of time sources.
313 Upgrade to 4.2.8p7, or later, from the NTP Project Download Page
314 or the NTP Public Services Project Download Page
315 If you are unable to upgrade and if you are running an OS that
316 has this vulnerability, implement martian packet filters and
317 lobby your OS vendor to fix this problem, or run your
318 refclocks on computers that use OSes that are not vulnerable
319 to these attacks and have your vulnerable machines get their
320 time from protected resources.
321 Properly monitor your ntpd instances.
322 Credit: This weakness was discovered by Matt Street and others of
323 Cisco ASIG.
324
325The following issues were fixed in earlier releases and contain
326improvements in 4.2.8p7:
327
328* Clients that receive a KoD should validate the origin timestamp field.
329 References: Sec 2901 / CVE-2015-7704, CVE-2015-7705
330 Affects: All ntp-4 releases up to, but not including 4.2.8p7,
331 Summary: Improvements to the fixes incorporated into 4.2.8p4 and 4.3.77.
332
333* Skeleton key: passive server with trusted key can serve time.
334 References: Sec 2936 / CVE-2015-7974
335 Affects: All ntp-4 releases up to, but not including 4.2.8p7,
336 Summary: Improvements to the fixes incorporated in t 4.2.8p6 and 4.3.90.
337
338Two other vulnerabilities have been reported, and the mitigations
339for these are as follows:
340
341* Interleave-pivot
342 Date Resolved: Stable (4.2.8p7) 26 Apr 2016; Dev (4.3.92) 26 Apr 2016
343 References: Sec 2978 / CVE-2016-1548
344 Affects: All ntp-4 releases.
345 CVSSv2: MED 6.4 - (AV:N/AC:L/Au:N/C:N/I:P/A:P)
346 CVSSv3: MED 7.2 - CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:L
347 Summary: It is possible to change the time of an ntpd client or deny
348 service to an ntpd client by forcing it to change from basic
349 client/server mode to interleaved symmetric mode. An attacker
350 can spoof a packet from a legitimate ntpd server with an origin
351 timestamp that matches the peer->dst timestamp recorded for that
352 server. After making this switch, the client will reject all
353 future legitimate server responses. It is possible to force the
354 victim client to move time after the mode has been changed.
355 ntpq gives no indication that the mode has been switched.
356 Mitigation:
357 Implement BCP-38.
358 Upgrade to 4.2.8p7, or later, from the NTP Project Download Page
359 or the NTP Public Services Project Download Page. These
360 versions will not dynamically "flip" into interleave mode
361 unless configured to do so.
362 Properly monitor your ntpd instances.
363 Credit: This weakness was discovered by Miroslav Lichvar of RedHat
364 and separately by Jonathan Gardner of Cisco ASIG.
365
366* Sybil vulnerability: ephemeral association attack
367 Date Resolved: Stable (4.2.8p7) 26 Apr 2016; Dev (4.3.92) 26 Apr 2016
368 References: Sec 3012 / CVE-2016-1549
369 Affects: All ntp-4 releases up to, but not including 4.2.8p7, and
370 4.3.0 up to, but not including 4.3.92
371 CVSSv2: LOW 3.5 - (AV:N/AC:M/Au:S/C:N/I:P/A:N)
372 CVSS3v: MED 5.3 - CVSS:3.0/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:N
373 Summary: ntpd can be vulnerable to Sybil attacks. If one is not using
374 the feature introduced in ntp-4.2.8p6 allowing an optional 4th
375 field in the ntp.keys file to specify which IPs can serve time,
376 a malicious authenticated peer can create arbitrarily-many
377 ephemeral associations in order to win the clock selection of
378 ntpd and modify a victim's clock.
379 Mitigation:
380 Implement BCP-38.
381 Use the 4th field in the ntp.keys file to specify which IPs
382 can be time servers.
383 Properly monitor your ntpd instances.
384 Credit: This weakness was discovered by Matthew Van Gundy of Cisco ASIG.
385
386Other fixes:
387
388* [Bug 2831] Segmentation Fault in DNS lookup during startup. perlinger@ntp.org
389 - fixed yet another race condition in the threaded resolver code.
390* [Bug 2858] bool support. Use stdbool.h when available. HStenn.
391* [Bug 2879] Improve NTP security against timing attacks. perlinger@ntp.org
392 - integrated patches by Loganaden Velvidron <logan@ntp.org>
393 with some modifications & unit tests
394* [Bug 2960] async name resolution fixes for chroot() environments.
395 Reinhard Max.
396* [Bug 2994] Systems with HAVE_SIGNALED_IO fail to compile. perlinger@ntp.org
397* [Bug 2995] Fixes to compile on Windows
398* [Bug 2999] out-of-bounds access in 'is_safe_filename()'. perlinger@ntp.org
399* [Bug 3013] Fix for ssl_init.c SHA1 test. perlinger@ntp.org
400 - Patch provided by Ch. Weisgerber
401* [Bug 3015] ntpq: config-from-file: "request contains an unprintable character"
402 - A change related to [Bug 2853] forbids trailing white space in
403 remote config commands. perlinger@ntp.org
404* [Bug 3019] NTPD stops processing packets after ERROR_HOST_UNREACHABLE
405 - report and patch from Aleksandr Kostikov.
406 - Overhaul of Windows IO completion port handling. perlinger@ntp.org
407* [Bug 3022] authkeys.c should be refactored. perlinger@ntp.org
408 - fixed memory leak in access list (auth[read]keys.c)
409 - refactored handling of key access lists (auth[read]keys.c)
410 - reduced number of error branches (authreadkeys.c)
411* [Bug 3023] ntpdate cannot correct dates in the future. perlinger@ntp.org
412* [Bug 3030] ntpq needs a general way to specify refid output format. HStenn.
413* [Bug 3031] ntp broadcastclient unable to synchronize to an server
414 when the time of server changed. perlinger@ntp.org
415 - Check the initial delay calculation and reject/unpeer the broadcast
416 server if the delay exceeds 50ms. Retry again after the next
417 broadcast packet.
418* [Bug 3036] autokey trips an INSIST in authistrustedip(). Harlan Stenn.
419* Document ntp.key's optional IP list in authenetic.html. Harlan Stenn.
420* Update html/xleave.html documentation. Harlan Stenn.
421* Update ntp.conf documentation. Harlan Stenn.
422* Fix some Credit: attributions in the NEWS file. Harlan Stenn.
423* Fix typo in html/monopt.html. Harlan Stenn.
424* Add README.pullrequests. Harlan Stenn.
425* Cleanup to include/ntp.h. Harlan Stenn.
426
427New option to 'configure':
428
429While looking in to the issues around Bug 2978, the "interleave pivot"
430issue, it became clear that there are some intricate and unresolved
431issues with interleave operations. We also realized that the interleave
432protocol was never added to the NTPv4 Standard, and it should have been.
433
434Interleave mode was first released in July of 2008, and can be engaged
435in two ways. Any 'peer' and 'broadcast' lines in the ntp.conf file may
436contain the 'xleave' option, which will expressly enable interlave mode
437for that association. Additionally, if a time packet arrives and is
438found inconsistent with normal protocol behavior but has certain
439characteristics that are compatible with interleave mode, NTP will
440dynamically switch to interleave mode. With sufficient knowledge, an
441attacker can send a crafted forged packet to an NTP instance that
442triggers only one side to enter interleaved mode.
443
444To prevent this attack until we can thoroughly document, describe,
445fix, and test the dynamic interleave mode, we've added a new
446'configure' option to the build process:
447
448 --enable-dynamic-interleave
449
450This option controls whether or not NTP will, if conditions are right,
451engage dynamic interleave mode. Dynamic interleave mode is disabled by
452default in ntp-4.2.8p7.
453
454---
455NTP 4.2.8p6 (Harlan Stenn <stenn@ntp.org>, 2016/01/20)
456
457Focus: Security, Bug fixes, enhancements.
458
459Severity: MEDIUM
460
461In addition to bug fixes and enhancements, this release fixes the
462following 1 low- and 8 medium-severity vulnerabilities:
463
464* Potential Infinite Loop in 'ntpq'
465 Date Resolved: Stable (4.2.8p6) 19 Jan 2016; Dev (4.3.90) 19 Jan 2016
466 References: Sec 2548 / CVE-2015-8158
467 Affects: All ntp-4 releases up to, but not including 4.2.8p6, and
468 4.3.0 up to, but not including 4.3.90
469 CVSS2: (AV:N/AC:M/Au:N/C:N/I:N/A:P) Base Score: 4.3 - MEDIUM
470 CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N Base Score: 5.3 - MEDIUM
471 Summary: 'ntpq' processes incoming packets in a loop in 'getresponse()'.
472 The loop's only stopping conditions are receiving a complete and
473 correct response or hitting a small number of error conditions.
474 If the packet contains incorrect values that don't trigger one of
475 the error conditions, the loop continues to receive new packets.
476 Note well, this is an attack against an instance of 'ntpq', not
477 'ntpd', and this attack requires the attacker to do one of the
478 following:
479 * Own a malicious NTP server that the client trusts
480 * Prevent a legitimate NTP server from sending packets to
481 the 'ntpq' client
482 * MITM the 'ntpq' communications between the 'ntpq' client
483 and the NTP server
484 Mitigation:
485 Upgrade to 4.2.8p6, or later, from the NTP Project Download Page
486 or the NTP Public Services Project Download Page
487 Credit: This weakness was discovered by Jonathan Gardner of Cisco ASIG.
488
489* 0rigin: Zero Origin Timestamp Bypass
490 Date Resolved: Stable (4.2.8p6) 19 Jan 2016; Dev (4.3.90) 19 Jan 2016
491 References: Sec 2945 / CVE-2015-8138
492 Affects: All ntp-4 releases up to, but not including 4.2.8p6, and
493 4.3.0 up to, but not including 4.3.90
494 CVSS2: (AV:N/AC:L/Au:N/C:N/I:P/A:N) Base Score: 5.0 - MEDIUM
495 CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N Base Score: 5.3 - MEDIUM
496 (3.7 - LOW if you score AC:L)
497 Summary: To distinguish legitimate peer responses from forgeries, a
498 client attempts to verify a response packet by ensuring that the
499 origin timestamp in the packet matches the origin timestamp it
500 transmitted in its last request. A logic error exists that
501 allows packets with an origin timestamp of zero to bypass this
502 check whenever there is not an outstanding request to the server.
503 Mitigation:
504 Configure 'ntpd' to get time from multiple sources.
505 Upgrade to 4.2.8p6, or later, from the NTP Project Download Page
506 or the NTP Public Services Project Download Page.
507 Monitor your 'ntpd= instances.
508 Credit: This weakness was discovered by Matthey Van Gundy and
509 Jonathan Gardner of Cisco ASIG.
510
511* Stack exhaustion in recursive traversal of restriction list
512 Date Resolved: Stable (4.2.8p6) 19 Jan 2016
513 References: Sec 2940 / CVE-2015-7978
514 Affects: All ntp-4 releases up to, but not including 4.2.8p6, and
515 4.3.0 up to, but not including 4.3.90
516 CVSS: (AV:N/AC:M/Au:N/C:N/I:N/A:P) Base Score: 4.3 - MEDIUM
517 Summary: An unauthenticated 'ntpdc reslist' command can cause a
518 segmentation fault in ntpd by exhausting the call stack.
519 Mitigation:
520 Implement BCP-38.
521 Upgrade to 4.2.8p6, or later, from the NTP Project Download Page
522 or the NTP Public Services Project Download Page.
523 If you are unable to upgrade:
524 In ntp-4.2.8, mode 7 is disabled by default. Don't enable it.
525 If you must enable mode 7:
526 configure the use of a 'requestkey' to control who can
527 issue mode 7 requests.
528 configure 'restrict noquery' to further limit mode 7
529 requests to trusted sources.
530 Monitor your ntpd instances.
531 Credit: This weakness was discovered by Stephen Gray at Cisco ASIG.
532
533* Off-path Denial of Service (!DoS) attack on authenticated broadcast mode
534 Date Resolved: Stable (4.2.8p6) 19 Jan 2016; Dev (4.3.90) 19 Jan 2016
535 References: Sec 2942 / CVE-2015-7979
536 Affects: All ntp-4 releases up to, but not including 4.2.8p6, and
537 4.3.0 up to, but not including 4.3.90
538 CVSS: (AV:N/AC:M/Au:N/C:N/I:P/A:P) Base Score: 5.8
539 Summary: An off-path attacker can send broadcast packets with bad
540 authentication (wrong key, mismatched key, incorrect MAC, etc)
541 to broadcast clients. It is observed that the broadcast client
542 tears down the association with the broadcast server upon
543 receiving just one bad packet.
544 Mitigation:
545 Implement BCP-38.
546 Upgrade to 4.2.8p6, or later, from the NTP Project Download Page
547 or the NTP Public Services Project Download Page.
548 Monitor your 'ntpd' instances.
549 If this sort of attack is an active problem for you, you have
550 deeper problems to investigate. In this case also consider
551 having smaller NTP broadcast domains.
552 Credit: This weakness was discovered by Aanchal Malhotra of Boston
553 University.
554
555* reslist NULL pointer dereference
556 Date Resolved: Stable (4.2.8p6) 19 Jan 2016; Dev (4.3.90) 19 Jan 2016
557 References: Sec 2939 / CVE-2015-7977
558 Affects: All ntp-4 releases up to, but not including 4.2.8p6, and
559 4.3.0 up to, but not including 4.3.90
560 CVSS: (AV:N/AC:M/Au:N/C:N/I:N/A:P) Base Score: 4.3 - MEDIUM
561 Summary: An unauthenticated 'ntpdc reslist' command can cause a
562 segmentation fault in ntpd by causing a NULL pointer dereference.
563 Mitigation:
564 Implement BCP-38.
565 Upgrade to 4.2.8p6, or later, from NTP Project Download Page or
566 the NTP Public Services Project Download Page.
567 If you are unable to upgrade:
568 mode 7 is disabled by default. Don't enable it.
569 If you must enable mode 7:
570 configure the use of a 'requestkey' to control who can
571 issue mode 7 requests.
572 configure 'restrict noquery' to further limit mode 7
573 requests to trusted sources.
574 Monitor your ntpd instances.
575 Credit: This weakness was discovered by Stephen Gray of Cisco ASIG.
576
577* 'ntpq saveconfig' command allows dangerous characters in filenames.
578 Date Resolved: Stable (4.2.8p6) 19 Jan 2016; Dev (4.3.90) 19 Jan 2016
579 References: Sec 2938 / CVE-2015-7976
580 Affects: All ntp-4 releases up to, but not including 4.2.8p6, and
581 4.3.0 up to, but not including 4.3.90
582 CVSS: (AV:N/AC:L/Au:S/C:N/I:P/A:N) Base Score: 4.0 - MEDIUM
583 Summary: The ntpq saveconfig command does not do adequate filtering
584 of special characters from the supplied filename.
585 Note well: The ability to use the saveconfig command is controlled
586 by the 'restrict nomodify' directive, and the recommended default
587 configuration is to disable this capability. If the ability to
588 execute a 'saveconfig' is required, it can easily (and should) be
589 limited and restricted to a known small number of IP addresses.
590 Mitigation:
591 Implement BCP-38.
592 use 'restrict default nomodify' in your 'ntp.conf' file.
593 Upgrade to 4.2.8p6, or later, from the NTP Project Download Page.
594 If you are unable to upgrade:
595 build NTP with 'configure --disable-saveconfig' if you will
596 never need this capability, or
597 use 'restrict default nomodify' in your 'ntp.conf' file. Be
598 careful about what IPs have the ability to send 'modify'
599 requests to 'ntpd'.
600 Monitor your ntpd instances.
601 'saveconfig' requests are logged to syslog - monitor your syslog files.
602 Credit: This weakness was discovered by Jonathan Gardner of Cisco ASIG.
603
604* nextvar() missing length check in ntpq
605 Date Resolved: Stable (4.2.8p6) 19 Jan 2016; Dev (4.3.90) 19 Jan 2016
606 References: Sec 2937 / CVE-2015-7975
607 Affects: All ntp-4 releases up to, but not including 4.2.8p6, and
608 4.3.0 up to, but not including 4.3.90
609 CVSS: (AV:L/AC:H/Au:N/C:N/I:N/A:P) Base Score: 1.2 - LOW
610 If you score A:C, this becomes 4.0.
611 CVSSv3: (CVSS:3.0/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L) Base Score 2.9, LOW
612 Summary: ntpq may call nextvar() which executes a memcpy() into the
613 name buffer without a proper length check against its maximum
614 length of 256 bytes. Note well that we're taking about ntpq here.
615 The usual worst-case effect of this vulnerability is that the
616 specific instance of ntpq will crash and the person or process
617 that did this will have stopped themselves.
618 Mitigation:
619 Upgrade to 4.2.8p6, or later, from the NTP Project Download Page
620 or the NTP Public Services Project Download Page.
621 If you are unable to upgrade:
622 If you have scripts that feed input to ntpq make sure there are
623 some sanity checks on the input received from the "outside".
624 This is potentially more dangerous if ntpq is run as root.
625 Credit: This weakness was discovered by Jonathan Gardner at Cisco ASIG.
626
627* Skeleton Key: Any trusted key system can serve time
628 Date Resolved: Stable (4.2.8p6) 19 Jan 2016; Dev (4.3.90) 19 Jan 2016
629 References: Sec 2936 / CVE-2015-7974
630 Affects: All ntp-4 releases up to, but not including 4.2.8p6, and
631 4.3.0 up to, but not including 4.3.90
632 CVSS: (AV:N/AC:H/Au:S/C:N/I:C/A:N) Base Score: 4.9
633 Summary: Symmetric key encryption uses a shared trusted key. The
634 reported title for this issue was "Missing key check allows
635 impersonation between authenticated peers" and the report claimed
636 "A key specified only for one server should only work to
637 authenticate that server, other trusted keys should be refused."
638 Except there has never been any correlation between this trusted
639 key and server v. clients machines and there has never been any
640 way to specify a key only for one server. We have treated this as
641 an enhancement request, and ntp-4.2.8p6 includes other checks and
642 tests to strengthen clients against attacks coming from broadcast
643 servers.
644 Mitigation:
645 Implement BCP-38.
646 If this scenario represents a real or a potential issue for you,
647 upgrade to 4.2.8p6, or later, from the NTP Project Download
648 Page or the NTP Public Services Project Download Page, and
649 use the new field in the ntp.keys file that specifies the list
650 of IPs that are allowed to serve time. Note that this alone
651 will not protect against time packets with forged source IP
652 addresses, however other changes in ntp-4.2.8p6 provide
653 significant mitigation against broadcast attacks. MITM attacks
654 are a different story.
655 If you are unable to upgrade:
656 Don't use broadcast mode if you cannot monitor your client
657 servers.
658 If you choose to use symmetric keys to authenticate time
659 packets in a hostile environment where ephemeral time
660 servers can be created, or if it is expected that malicious
661 time servers will participate in an NTP broadcast domain,
662 limit the number of participating systems that participate
663 in the shared-key group.
664 Monitor your ntpd instances.
665 Credit: This weakness was discovered by Matt Street of Cisco ASIG.
666
667* Deja Vu: Replay attack on authenticated broadcast mode
668 Date Resolved: Stable (4.2.8p6) 19 Jan 2016; Dev (4.3.90) 19 Jan 2016
669 References: Sec 2935 / CVE-2015-7973
670 Affects: All ntp-4 releases up to, but not including 4.2.8p6, and
671 4.3.0 up to, but not including 4.3.90
672 CVSS: (AV:A/AC:M/Au:N/C:N/I:P/A:P) Base Score: 4.3 - MEDIUM
673 Summary: If an NTP network is configured for broadcast operations then
674 either a man-in-the-middle attacker or a malicious participant
675 that has the same trusted keys as the victim can replay time packets.
676 Mitigation:
677 Implement BCP-38.
678 Upgrade to 4.2.8p6, or later, from the NTP Project Download Page
679 or the NTP Public Services Project Download Page.
680 If you are unable to upgrade:
681 Don't use broadcast mode if you cannot monitor your client servers.
682 Monitor your ntpd instances.
683 Credit: This weakness was discovered by Aanchal Malhotra of Boston
684 University.
685
686Other fixes:
687
688* [Bug 2772] adj_systime overflows tv_usec. perlinger@ntp.org
689* [Bug 2814] msyslog deadlock when signaled. perlinger@ntp.org
690 - applied patch by shenpeng11@huawei.com with minor adjustments
691* [Bug 2882] Look at ntp_request.c:list_peers_sum(). perlinger@ntp.org
692* [Bug 2891] Deadlock in deferred DNS lookup framework. perlinger@ntp.org
693* [Bug 2892] Several test cases assume IPv6 capabilities even when
694 IPv6 is disabled in the build. perlinger@ntp.org
695 - Found this already fixed, but validation led to cleanup actions.
696* [Bug 2905] DNS lookups broken. perlinger@ntp.org
697 - added limits to stack consumption, fixed some return code handling
698* [Bug 2971] ntpq bails on ^C: select fails: Interrupted system call
699 - changed stacked/nested handling of CTRL-C. perlinger@ntp.org
700 - make CTRL-C work for retrieval and printing od MRU list. perlinger@ntp.org
701* [Bug 2980] reduce number of warnings. perlinger@ntp.org
702 - integrated several patches from Havard Eidnes (he@uninett.no)
703* [Bug 2985] bogus calculation in authkeys.c perlinger@ntp.org
704 - implement 'auth_log2()' using integer bithack instead of float calculation
705* Make leapsec_query debug messages less verbose. Harlan Stenn.
706
707---
708NTP 4.2.8p5 (Harlan Stenn <stenn@ntp.org>, 2016/01/07)
709
710Focus: Security, Bug fixes, enhancements.
711
712Severity: MEDIUM
713
714In addition to bug fixes and enhancements, this release fixes the
715following medium-severity vulnerability:
716
717* Small-step/big-step. Close the panic gate earlier.
718 References: Sec 2956, CVE-2015-5300
719 Affects: All ntp-4 releases up to, but not including 4.2.8p5, and
720 4.3.0 up to, but not including 4.3.78
721 CVSS3: (AV:N/AC:H/PR:H/UI:R/S:C/C:L/I:N/A:L) Base Score: 4.0, MEDIUM
722 Summary: If ntpd is always started with the -g option, which is
723 common and against long-standing recommendation, and if at the
724 moment ntpd is restarted an attacker can immediately respond to
725 enough requests from enough sources trusted by the target, which
726 is difficult and not common, there is a window of opportunity
727 where the attacker can cause ntpd to set the time to an
728 arbitrary value. Similarly, if an attacker is able to respond
729 to enough requests from enough sources trusted by the target,
730 the attacker can cause ntpd to abort and restart, at which
731 point it can tell the target to set the time to an arbitrary
732 value if and only if ntpd was re-started against long-standing
733 recommendation with the -g flag, or if ntpd was not given the
734 -g flag, the attacker can move the target system's time by at
735 most 900 seconds' time per attack.
736 Mitigation:
737 Configure ntpd to get time from multiple sources.
738 Upgrade to 4.2.8p5, or later, from the NTP Project Download
739 Page or the NTP Public Services Project Download Page
740 As we've long documented, only use the -g option to ntpd in
741 cold-start situations.
742 Monitor your ntpd instances.
743 Credit: This weakness was discovered by Aanchal Malhotra,
744 Isaac E. Cohen, and Sharon Goldberg at Boston University.
745
746 NOTE WELL: The -g flag disables the limit check on the panic_gate
747 in ntpd, which is 900 seconds by default. The bug identified by
748 the researchers at Boston University is that the panic_gate
749 check was only re-enabled after the first change to the system
750 clock that was greater than 128 milliseconds, by default. The
751 correct behavior is that the panic_gate check should be
752 re-enabled after any initial time correction.
753
754 If an attacker is able to inject consistent but erroneous time
755 responses to your systems via the network or "over the air",
756 perhaps by spoofing radio, cellphone, or navigation satellite
757 transmissions, they are in a great position to affect your
758 system's clock. There comes a point where your very best
759 defenses include:
760
761 Configure ntpd to get time from multiple sources.
762 Monitor your ntpd instances.
763
764Other fixes:
765
766* Coverity submission process updated from Coverity 5 to Coverity 7.
767 The NTP codebase has been undergoing regular Coverity scans on an
768 ongoing basis since 2006. As part of our recent upgrade from
769 Coverity 5 to Coverity 7, Coverity identified 16 nits in some of
770 the newly-written Unity test programs. These were fixed.
771* [Bug 2829] Clean up pipe_fds in ntpd.c perlinger@ntp.org
772* [Bug 2887] stratum -1 config results as showing value 99
773 - fudge stratum should only accept values [0..16]. perlinger@ntp.org
774* [Bug 2932] Update leapsecond file info in miscopt.html. CWoodbury, HStenn.
775* [Bug 2934] tests/ntpd/t-ntp_scanner.c has a magic constant wired in. HMurray
776* [Bug 2944] errno is not preserved properly in ntpdate after sendto call.
777 - applied patch by Christos Zoulas. perlinger@ntp.org
778* [Bug 2952] Peer associations broken by fix for Bug 2901/CVE-2015-7704.
779* [Bug 2954] Version 4.2.8p4 crashes on startup on some OSes.
780 - fixed data race conditions in threaded DNS worker. perlinger@ntp.org
781 - limit threading warm-up to linux; FreeBSD bombs on it. perlinger@ntp.org
782* [Bug 2957] 'unsigned int' vs 'size_t' format clash. perlinger@ntp.org
783 - accept key file only if there are no parsing errors
784 - fixed size_t/u_int format clash
785 - fixed wrong use of 'strlcpy'
786* [Bug 2958] ntpq: fatal error messages need a final newline. Craig Leres.
787* [Bug 2962] truncation of size_t/ptrdiff_t on 64bit targets. perlinger@ntp.org
788 - fixed several other warnings (cast-alignment, missing const, missing prototypes)
789 - promote use of 'size_t' for values that express a size
790 - use ptr-to-const for read-only arguments
791 - make sure SOCKET values are not truncated (win32-specific)
792 - format string fixes
793* [Bug 2965] Local clock didn't work since 4.2.8p4. Martin Burnicki.
794* [Bug 2967] ntpdate command suffers an assertion failure
795 - fixed ntp_rfc2553.c to return proper address length. perlinger@ntp.org
796* [Bug 2969] Seg fault from ntpq/mrulist when looking at server with
797 lots of clients. perlinger@ntp.org
798* [Bug 2971] ntpq bails on ^C: select fails: Interrupted system call
799 - changed stacked/nested handling of CTRL-C. perlinger@ntp.org
800* Unity cleanup for FreeBSD-6.4. Harlan Stenn.
801* Unity test cleanup. Harlan Stenn.
802* Libevent autoconf pthread fixes for FreeBSD-10. Harlan Stenn.
803* Header cleanup in tests/sandbox/uglydate.c. Harlan Stenn.
804* Header cleanup in tests/libntp/sfptostr.c. Harlan Stenn.
805* Quiet a warning from clang. Harlan Stenn.
806
807---
808NTP 4.2.8p4 (Harlan Stenn <stenn@ntp.org>, 2015/10/21)
809
810Focus: Security, Bug fixes, enhancements.
811
812Severity: MEDIUM
813
814In addition to bug fixes and enhancements, this release fixes the
815following 13 low- and medium-severity vulnerabilities:
816
817* Incomplete vallen (value length) checks in ntp_crypto.c, leading
818 to potential crashes or potential code injection/information leakage.
819
820 References: Sec 2899, Sec 2671, CVE-2015-7691, CVE-2015-7692, CVE-2015-7702
821 Affects: All ntp-4 releases up to, but not including 4.2.8p4,
822 and 4.3.0 up to, but not including 4.3.77
823 CVSS: (AV:N/AC:H/Au:M/C:N/I:N/A:C) Base Score: 4.6
824 Summary: The fix for CVE-2014-9750 was incomplete in that there were
825 certain code paths where a packet with particular autokey operations
826 that contained malicious data was not always being completely
827 validated. Receipt of these packets can cause ntpd to crash.
828 Mitigation:
829 Don't use autokey.
830 Upgrade to 4.2.8p4, or later, from the NTP Project Download
831 Page or the NTP Public Services Project Download Page
832 Monitor your ntpd instances.
833 Credit: This weakness was discovered by Tenable Network Security.
834
835* Clients that receive a KoD should validate the origin timestamp field.
836
837 References: Sec 2901 / CVE-2015-7704, CVE-2015-7705
838 Affects: All ntp-4 releases up to, but not including 4.2.8p4,
839 and 4.3.0 up to, but not including 4.3.77
840 CVSS: (AV:N/AC:M/Au:N/C:N/I:N/A:P) Base Score: 4.3-5.0 at worst
841 Summary: An ntpd client that honors Kiss-of-Death responses will honor
842 KoD messages that have been forged by an attacker, causing it to
843 delay or stop querying its servers for time updates. Also, an
844 attacker can forge packets that claim to be from the target and
845 send them to servers often enough that a server that implements
846 KoD rate limiting will send the target machine a KoD response to
847 attempt to reduce the rate of incoming packets, or it may also
848 trigger a firewall block at the server for packets from the target
849 machine. For either of these attacks to succeed, the attacker must
850 know what servers the target is communicating with. An attacker
851 can be anywhere on the Internet and can frequently learn the
852 identity of the target's time source by sending the target a
853 time query.
854 Mitigation:
855 Implement BCP-38.
856 Upgrade to 4.2.8p4, or later, from the NTP Project Download Page
857 or the NTP Public Services Project Download Page
858 If you can't upgrade, restrict who can query ntpd to learn who
859 its servers are, and what IPs are allowed to ask your system
860 for the time. This mitigation is heavy-handed.
861 Monitor your ntpd instances.
862 Note:
863 4.2.8p4 protects against the first attack. For the second attack,
864 all we can do is warn when it is happening, which we do in 4.2.8p4.
865 Credit: This weakness was discovered by Aanchal Malhotra,
866 Issac E. Cohen, and Sharon Goldberg of Boston University.
867
868* configuration directives to change "pidfile" and "driftfile" should
869 only be allowed locally.
870
871 References: Sec 2902 / CVE-2015-5196
872 Affects: All ntp-4 releases up to, but not including 4.2.8p4,
873 and 4.3.0 up to, but not including 4.3.77
874 CVSS: (AV:N/AC:H/Au:M/C:N/I:C/A:C) Base Score: 6.2 worst case
875 Summary: If ntpd is configured to allow for remote configuration,
876 and if the (possibly spoofed) source IP address is allowed to
877 send remote configuration requests, and if the attacker knows
878 the remote configuration password, it's possible for an attacker
879 to use the "pidfile" or "driftfile" directives to potentially
880 overwrite other files.
881 Mitigation:
882 Implement BCP-38.
883 Upgrade to 4.2.8p4, or later, from the NTP Project Download
884 Page or the NTP Public Services Project Download Page
885 If you cannot upgrade, don't enable remote configuration.
886 If you must enable remote configuration and cannot upgrade,
887 remote configuration of NTF's ntpd requires:
888 - an explicitly configured trustedkey, and you should also
889 configure a controlkey.
890 - access from a permitted IP. You choose the IPs.
891 - authentication. Don't disable it. Practice secure key safety.
892 Monitor your ntpd instances.
893 Credit: This weakness was discovered by Miroslav Lichvar of Red Hat.
894
895* Slow memory leak in CRYPTO_ASSOC
896
897 References: Sec 2909 / CVE-2015-7701
898 Affects: All ntp-4 releases that use autokey up to, but not
899 including 4.2.8p4, and 4.3.0 up to, but not including 4.3.77
900 CVSS: (AV:N/AC:H/Au:M/C:N/I:N/A:C) Base Score: 0.0 best/usual case,
901 4.6 otherwise
902 Summary: If ntpd is configured to use autokey, then an attacker can
903 send packets to ntpd that will, after several days of ongoing
904 attack, cause it to run out of memory.
905 Mitigation:
906 Don't use autokey.
907 Upgrade to 4.2.8p4, or later, from the NTP Project Download
908 Page or the NTP Public Services Project Download Page
909 Monitor your ntpd instances.
910 Credit: This weakness was discovered by Tenable Network Security.
911
912* mode 7 loop counter underrun
913
914 References: Sec 2913 / CVE-2015-7848 / TALOS-CAN-0052
915 Affects: All ntp-4 releases up to, but not including 4.2.8p4,
916 and 4.3.0 up to, but not including 4.3.77
917 CVSS: (AV:N/AC:H/Au:M/C:N/I:N/A:C) Base Score: 4.6
918 Summary: If ntpd is configured to enable mode 7 packets, and if the
919 use of mode 7 packets is not properly protected thru the use of
920 the available mode 7 authentication and restriction mechanisms,
921 and if the (possibly spoofed) source IP address is allowed to
922 send mode 7 queries, then an attacker can send a crafted packet
923 to ntpd that will cause it to crash.
924 Mitigation:
925 Implement BCP-38.
926 Upgrade to 4.2.8p4, or later, from the NTP Project Download
927 Page or the NTP Public Services Project Download Page.
928 If you are unable to upgrade:
929 In ntp-4.2.8, mode 7 is disabled by default. Don't enable it.
930 If you must enable mode 7:
931 configure the use of a requestkey to control who can issue
932 mode 7 requests.
933 configure restrict noquery to further limit mode 7 requests
934 to trusted sources.
935 Monitor your ntpd instances.
936Credit: This weakness was discovered by Aleksandar Nikolic of Cisco Talos.
937
938* memory corruption in password store
939
940 References: Sec 2916 / CVE-2015-7849 / TALOS-CAN-0054
941 Affects: All ntp-4 releases up to, but not including 4.2.8p4, and 4.3.0 up to, but not including 4.3.77
942 CVSS: (AV:N/AC:H/Au:M/C:N/I:C/A:C) Base Score: 6.8, worst case
943 Summary: If ntpd is configured to allow remote configuration, and if
944 the (possibly spoofed) source IP address is allowed to send
945 remote configuration requests, and if the attacker knows the
946 remote configuration password or if ntpd was configured to
947 disable authentication, then an attacker can send a set of
948 packets to ntpd that may cause a crash or theoretically
949 perform a code injection attack.
950 Mitigation:
951 Implement BCP-38.
952 Upgrade to 4.2.8p4, or later, from the NTP Project Download
953 Page or the NTP Public Services Project Download Page.
954 If you are unable to upgrade, remote configuration of NTF's
955 ntpd requires:
956 an explicitly configured "trusted" key. Only configure
957 this if you need it.
958 access from a permitted IP address. You choose the IPs.
959 authentication. Don't disable it. Practice secure key safety.
960 Monitor your ntpd instances.
961 Credit: This weakness was discovered by Yves Younan of Cisco Talos.
962
963* Infinite loop if extended logging enabled and the logfile and
964 keyfile are the same.
965
966 References: Sec 2917 / CVE-2015-7850 / TALOS-CAN-0055
967 Affects: All ntp-4 releases up to, but not including 4.2.8p4,
968 and 4.3.0 up to, but not including 4.3.77
969 CVSS: (AV:N/AC:H/Au:M/C:N/I:N/A:C) Base Score: 4.6, worst case
970 Summary: If ntpd is configured to allow remote configuration, and if
971 the (possibly spoofed) source IP address is allowed to send
972 remote configuration requests, and if the attacker knows the
973 remote configuration password or if ntpd was configured to
974 disable authentication, then an attacker can send a set of
975 packets to ntpd that will cause it to crash and/or create a
976 potentially huge log file. Specifically, the attacker could
977 enable extended logging, point the key file at the log file,
978 and cause what amounts to an infinite loop.
979 Mitigation:
980 Implement BCP-38.
981 Upgrade to 4.2.8p4, or later, from the NTP Project Download
982 Page or the NTP Public Services Project Download Page.
983 If you are unable to upgrade, remote configuration of NTF's ntpd
984 requires:
985 an explicitly configured "trusted" key. Only configure this
986 if you need it.
987 access from a permitted IP address. You choose the IPs.
988 authentication. Don't disable it. Practice secure key safety.
989 Monitor your ntpd instances.
990 Credit: This weakness was discovered by Yves Younan of Cisco Talos.
991
992* Potential path traversal vulnerability in the config file saving of
993 ntpd on VMS.
994
995 References: Sec 2918 / CVE-2015-7851 / TALOS-CAN-0062
996 Affects: All ntp-4 releases running under VMS up to, but not
997 including 4.2.8p4, and 4.3.0 up to, but not including 4.3.77
998 CVSS: (AV:N/AC:H/Au:M/C:N/I:P/A:C) Base Score: 5.2, worst case
999 Summary: If ntpd is configured to allow remote configuration, and if
1000 the (possibly spoofed) IP address is allowed to send remote
1001 configuration requests, and if the attacker knows the remote
1002 configuration password or if ntpd was configured to disable
1003 authentication, then an attacker can send a set of packets to
1004 ntpd that may cause ntpd to overwrite files.
1005 Mitigation:
1006 Implement BCP-38.
1007 Upgrade to 4.2.8p4, or later, from the NTP Project Download
1008 Page or the NTP Public Services Project Download Page.
1009 If you are unable to upgrade, remote configuration of NTF's ntpd
1010 requires:
1011 an explicitly configured "trusted" key. Only configure
1012 this if you need it.
1013 access from permitted IP addresses. You choose the IPs.
1014 authentication. Don't disable it. Practice key security safety.
1015 Monitor your ntpd instances.
1016 Credit: This weakness was discovered by Yves Younan of Cisco Talos.
1017
1018* ntpq atoascii() potential memory corruption
1019
1020 References: Sec 2919 / CVE-2015-7852 / TALOS-CAN-0063
1021 Affects: All ntp-4 releases running up to, but not including 4.2.8p4,
1022 and 4.3.0 up to, but not including 4.3.77
1023 CVSS: (AV:N/AC:H/Au:N/C:N/I:P/A:P) Base Score: 4.0, worst case
1024 Summary: If an attacker can figure out the precise moment that ntpq
1025 is listening for data and the port number it is listening on or
1026 if the attacker can provide a malicious instance ntpd that
1027 victims will connect to then an attacker can send a set of
1028 crafted mode 6 response packets that, if received by ntpq,
1029 can cause ntpq to crash.
1030 Mitigation:
1031 Implement BCP-38.
1032 Upgrade to 4.2.8p4, or later, from the NTP Project Download
1033 Page or the NTP Public Services Project Download Page.
1034 If you are unable to upgrade and you run ntpq against a server
1035 and ntpq crashes, try again using raw mode. Build or get a
1036 patched ntpq and see if that fixes the problem. Report new
1037 bugs in ntpq or abusive servers appropriately.
1038 If you use ntpq in scripts, make sure ntpq does what you expect
1039 in your scripts.
1040 Credit: This weakness was discovered by Yves Younan and
1041 Aleksander Nikolich of Cisco Talos.
1042
1043* Invalid length data provided by a custom refclock driver could cause
1044 a buffer overflow.
1045
1046 References: Sec 2920 / CVE-2015-7853 / TALOS-CAN-0064
1047 Affects: Potentially all ntp-4 releases running up to, but not
1048 including 4.2.8p4, and 4.3.0 up to, but not including 4.3.77
1049 that have custom refclocks
1050 CVSS: (AV:L/AC:H/Au:M/C:C/I:C/A:C) Base Score: 0.0 usual case,
1051 5.9 unusual worst case
1052 Summary: A negative value for the datalen parameter will overflow a
1053 data buffer. NTF's ntpd driver implementations always set this
1054 value to 0 and are therefore not vulnerable to this weakness.
1055 If you are running a custom refclock driver in ntpd and that
1056 driver supplies a negative value for datalen (no custom driver
1057 of even minimal competence would do this) then ntpd would
1058 overflow a data buffer. It is even hypothetically possible
1059 in this case that instead of simply crashing ntpd the attacker
1060 could effect a code injection attack.
1061 Mitigation:
1062 Upgrade to 4.2.8p4, or later, from the NTP Project Download
1063 Page or the NTP Public Services Project Download Page.
1064 If you are unable to upgrade:
1065 If you are running custom refclock drivers, make sure
1066 the signed datalen value is either zero or positive.
1067 Monitor your ntpd instances.
1068 Credit: This weakness was discovered by Yves Younan of Cisco Talos.
1069
1070* Password Length Memory Corruption Vulnerability
1071
1072 References: Sec 2921 / CVE-2015-7854 / TALOS-CAN-0065
1073 Affects: All ntp-4 releases up to, but not including 4.2.8p4, and
1074 4.3.0 up to, but not including 4.3.77
1075 CVSS: (AV:N/AC:H/Au:M/C:C/I:C/A:C) Base Score: 0.0 best case,
1076 1.7 usual case, 6.8, worst case
1077 Summary: If ntpd is configured to allow remote configuration, and if
1078 the (possibly spoofed) source IP address is allowed to send
1079 remote configuration requests, and if the attacker knows the
1080 remote configuration password or if ntpd was (foolishly)
1081 configured to disable authentication, then an attacker can
1082 send a set of packets to ntpd that may cause it to crash,
1083 with the hypothetical possibility of a small code injection.
1084 Mitigation:
1085 Implement BCP-38.
1086 Upgrade to 4.2.8p4, or later, from the NTP Project Download
1087 Page or the NTP Public Services Project Download Page.
1088 If you are unable to upgrade, remote configuration of NTF's
1089 ntpd requires:
1090 an explicitly configured "trusted" key. Only configure
1091 this if you need it.
1092 access from a permitted IP address. You choose the IPs.
1093 authentication. Don't disable it. Practice secure key safety.
1094 Monitor your ntpd instances.
1095 Credit: This weakness was discovered by Yves Younan and
1096 Aleksander Nikolich of Cisco Talos.
1097
1098* decodenetnum() will ASSERT botch instead of returning FAIL on some
1099 bogus values.
1100
1101 References: Sec 2922 / CVE-2015-7855
1102 Affects: All ntp-4 releases up to, but not including 4.2.8p4, and
1103 4.3.0 up to, but not including 4.3.77
1104 CVSS: (AV:N/AC:H/Au:M/C:N/I:N/A:C) Base Score: 4.6, worst case
1105 Summary: If ntpd is fed a crafted mode 6 or mode 7 packet containing
1106 an unusually long data value where a network address is expected,
1107 the decodenetnum() function will abort with an assertion failure
1108 instead of simply returning a failure condition.
1109 Mitigation:
1110 Implement BCP-38.
1111 Upgrade to 4.2.8p4, or later, from the NTP Project Download
1112 Page or the NTP Public Services Project Download Page.
1113 If you are unable to upgrade:
1114 mode 7 is disabled by default. Don't enable it.
1115 Use restrict noquery to limit who can send mode 6
1116 and mode 7 requests.
1117 Configure and use the controlkey and requestkey
1118 authentication directives to limit who can
1119 send mode 6 and mode 7 requests.
1120 Monitor your ntpd instances.
1121 Credit: This weakness was discovered by John D "Doug" Birdwell of IDA.org.
1122
1123* NAK to the Future: Symmetric association authentication bypass via
1124 crypto-NAK.
1125
1126 References: Sec 2941 / CVE-2015-7871
1127 Affects: All ntp-4 releases between 4.2.5p186 up to but not including
1128 4.2.8p4, and 4.3.0 up to but not including 4.3.77
1129 CVSS: (AV:N/AC:L/Au:N/C:N/I:P/A:P) Base Score: 6.4
1130 Summary: Crypto-NAK packets can be used to cause ntpd to accept time
1131 from unauthenticated ephemeral symmetric peers by bypassing the
1132 authentication required to mobilize peer associations. This
1133 vulnerability appears to have been introduced in ntp-4.2.5p186
1134 when the code handling mobilization of new passive symmetric
1135 associations (lines 1103-1165) was refactored.
1136 Mitigation:
1137 Implement BCP-38.
1138 Upgrade to 4.2.8p4, or later, from the NTP Project Download
1139 Page or the NTP Public Services Project Download Page.
1140 If you are unable to upgrade:
1141 Apply the patch to the bottom of the "authentic" check
1142 block around line 1136 of ntp_proto.c.
1143 Monitor your ntpd instances.
1144 Credit: This weakness was discovered by Matthew Van Gundy of Cisco ASIG.
1145
1146Backward-Incompatible changes:
1147* [Bug 2817] Default on Linux is now "rlimit memlock -1".
1148 While the general default of 32M is still the case, under Linux
1149 the default value has been changed to -1 (do not lock ntpd into
1150 memory). A value of 0 means "lock ntpd into memory with whatever
1151 memory it needs." If your ntp.conf file has an explicit "rlimit memlock"
1152 value in it, that value will continue to be used.
1153
1154* [Bug 2886] Misspelling: "outlyer" should be "outlier".
1155 If you've written a script that looks for this case in, say, the
1156 output of ntpq, you probably want to change your regex matches
1157 from 'outlyer' to 'outl[iy]er'.
1158
1159New features in this release:
1160* 'rlimit memlock' now has finer-grained control. A value of -1 means
1161 "don't lock ntpd into memore". This is the default for Linux boxes.
1162 A value of 0 means "lock ntpd into memory" with no limits. Otherwise
1163 the value is the number of megabytes of memory to lock. The default
1164 is 32 megabytes.
1165
1166* The old Google Test framework has been replaced with a new framework,
1167 based on http://www.throwtheswitch.org/unity/ .
1168
1169Bug Fixes and Improvements:
1170* [Bug 2332] (reopened) Exercise thread cancellation once before dropping
1171 privileges and limiting resources in NTPD removes the need to link
1172 forcefully against 'libgcc_s' which does not always work. J.Perlinger
1173* [Bug 2595] ntpdate man page quirks. Hal Murray, Harlan Stenn.
1174* [Bug 2625] Deprecate flag1 in local refclock. Hal Murray, Harlan Stenn.
1175* [Bug 2817] Stop locking ntpd into memory by default under Linux. H.Stenn.
1176* [Bug 2821] minor build issues: fixed refclock_gpsdjson.c. perlinger@ntp.org
1177* [Bug 2823] ntpsweep with recursive peers option doesn't work. H.Stenn.
1178* [Bug 2849] Systems with more than one default route may never
1179 synchronize. Brian Utterback. Note that this patch might need to
1180 be reverted once Bug 2043 has been fixed.
1181* [Bug 2864] 4.2.8p3 fails to compile on Windows. Juergen Perlinger
1182* [Bug 2866] segmentation fault at initgroups(). Harlan Stenn.
1183* [Bug 2867] ntpd with autokey active crashed by 'ntpq -crv'. J.Perlinger
1184* [Bug 2873] libevent should not include .deps/ in the tarball. H.Stenn
1185* [Bug 2874] Don't distribute generated sntp/tests/fileHandlingTest.h. H.Stenn
1186* [Bug 2875] sntp/Makefile.am: Get rid of DIST_SUBDIRS. libevent must
1187 be configured for the distribution targets. Harlan Stenn.
1188* [Bug 2883] ntpd crashes on exit with empty driftfile. Miroslav Lichvar.
1189* [Bug 2886] Mis-spelling: "outlyer" should be "outlier". dave@horsfall.org
1190* [Bug 2888] streamline calendar functions. perlinger@ntp.org
1191* [Bug 2889] ntp-dev-4.3.67 does not build on Windows. perlinger@ntp.org
1192* [Bug 2890] Ignore ENOBUFS on routing netlink socket. Konstantin Khlebnikov.
1193* [Bug 2906] make check needs better support for pthreads. Harlan Stenn.
1194* [Bug 2907] dist* build targets require our libevent/ to be enabled. HStenn.
1195* [Bug 2912] no munlockall() under Windows. David Taylor, Harlan Stenn.
1196* libntp/emalloc.c: Remove explicit include of stdint.h. Harlan Stenn.
1197* Put Unity CPPFLAGS items in unity_config.h. Harlan Stenn.
1198* tests/ntpd/g_leapsec.cpp typo fix. Harlan Stenn.
1199* Phase 1 deprecation of google test in sntp/tests/. Harlan Stenn.
1200* On some versions of HP-UX, inttypes.h does not include stdint.h. H.Stenn.
1201* top_srcdir can change based on ntp v. sntp. Harlan Stenn.
1202* sntp/tests/ function parameter list cleanup. Damir Tomi��.
1203* tests/libntp/ function parameter list cleanup. Damir Tomi��.
1204* tests/ntpd/ function parameter list cleanup. Damir Tomi��.
1205* sntp/unity/unity_config.h: handle stdint.h. Harlan Stenn.
1206* sntp/unity/unity_internals.h: handle *INTPTR_MAX on old Solaris. H.Stenn.
1207* tests/libntp/timevalops.c and timespecops.c fixed error printing. D.Tomi��.
1208* tests/libntp/ improvements in code and fixed error printing. Damir Tomi��.
1209* tests/libntp: a_md5encrypt.c, authkeys.c, buftvtots.c, calendar.c, caljulian.c,
1210 caltontp.c, clocktime.c, humandate.c, hextolfp.c, decodenetnum.c - fixed
1211 formatting; first declaration, then code (C90); deleted unnecessary comments;
1212 changed from sprintf to snprintf; fixed order of includes. Tomasz Flendrich
1213* tests/libntp/lfpfunc.c remove unnecessary include, remove old comments,
1214 fix formatting, cleanup. Tomasz Flendrich
1215* tests/libntp/lfptostr.c remove unnecessary include, add consts, fix formatting.
1216 Tomasz Flendrich
1217* tests/libntp/statestr.c remove empty functions, remove unnecessary include,
1218 fix formatting. Tomasz Flendrich
1219* tests/libntp/modetoa.c fixed formatting. Tomasz Flendrich
1220* tests/libntp/msyslog.c fixed formatting. Tomasz Flendrich
1221* tests/libntp/numtoa.c deleted unnecessary empty functions, fixed formatting.
1222 Tomasz Flendrich
1223* tests/libntp/numtohost.c added const, fixed formatting. Tomasz Flendrich
1224* tests/libntp/refnumtoa.c fixed formatting. Tomasz Flendrich
1225* tests/libntp/ssl_init.c fixed formatting. Tomasz Flendrich
1226* tests/libntp/tvtots.c fixed a bug, fixed formatting. Tomasz Flendrich
1227* tests/libntp/uglydate.c removed an unnecessary include. Tomasz Flendrich
1228* tests/libntp/vi64ops.c removed an unnecessary comment, fixed formatting.
1229* tests/libntp/ymd3yd.c removed an empty function and an unnecessary include,
1230fixed formatting. Tomasz Flendrich
1231* tests/libntp/timespecops.c fixed formatting, fixed the order of includes,
1232 removed unnecessary comments, cleanup. Tomasz Flendrich
1233* tests/libntp/timevalops.c fixed the order of includes, deleted unnecessary
1234 comments, cleanup. Tomasz Flendrich
1235* tests/libntp/sockaddrtest.h making it agree to NTP's conventions of formatting.
1236 Tomasz Flendrich
1237* tests/libntp/lfptest.h cleanup. Tomasz Flendrich
1238* tests/libntp/test-libntp.c fix formatting. Tomasz Flendrich
1239* sntp/tests/crypto.c is now using proper Unity's assertions, fixed formatting.
1240 Tomasz Flendrich
1241* sntp/tests/kodDatabase.c added consts, deleted empty function,
1242 fixed formatting. Tomasz Flendrich
1243* sntp/tests/kodFile.c cleanup, fixed formatting. Tomasz Flendrich
1244* sntp/tests/packetHandling.c is now using proper Unity's assertions,
1245 fixed formatting, deleted unused variable. Tomasz Flendrich
1246* sntp/tests/keyFile.c is now using proper Unity's assertions, fixed formatting.
1247 Tomasz Flendrich
1248* sntp/tests/packetProcessing.c changed from sprintf to snprintf,
1249 fixed formatting. Tomasz Flendrich
1250* sntp/tests/utilities.c is now using proper Unity's assertions, changed
1251 the order of includes, fixed formatting, removed unnecessary comments.
1252 Tomasz Flendrich
1253* sntp/tests/sntptest.h fixed formatting. Tomasz Flendrich
1254* sntp/tests/fileHandlingTest.h.in fixed a possible buffer overflow problem,
1255 made one function do its job, deleted unnecessary prints, fixed formatting.
1256 Tomasz Flendrich
1257* sntp/unity/Makefile.am added a missing header. Tomasz Flendrich
1258* sntp/unity/unity_config.h: Distribute it. Harlan Stenn.
1259* sntp/libevent/evconfig-private.h: remove generated filefrom SCM. H.Stenn.
1260* sntp/unity/Makefile.am: fix some broken paths. Harlan Stenn.
1261* sntp/unity/unity.c: Clean up a printf(). Harlan Stenn.
1262* Phase 1 deprecation of google test in tests/libntp/. Harlan Stenn.
1263* Don't build sntp/libevent/sample/. Harlan Stenn.
1264* tests/libntp/test_caltontp needs -lpthread. Harlan Stenn.
1265* br-flock: --enable-local-libevent. Harlan Stenn.
1266* Wrote tests for ntpd/ntp_prio_q.c. Tomasz Flendrich
1267* scripts/lib/NTP/Util.pm: stratum output is version-dependent. Harlan Stenn.
1268* Get rid of the NTP_ prefix on our assertion macros. Harlan Stenn.
1269* Code cleanup. Harlan Stenn.
1270* libntp/icom.c: Typo fix. Harlan Stenn.
1271* util/ntptime.c: initialization nit. Harlan Stenn.
1272* ntpd/ntp_peer.c:newpeer(): added a DEBUG_REQUIRE(srcadr). Harlan Stenn.
1273* Add std_unity_tests to various Makefile.am files. Harlan Stenn.
1274* ntpd/ntp_restrict.c: added a few assertions, created tests for this file.
1275 Tomasz Flendrich
1276* Changed progname to be const in many files - now it's consistent. Tomasz
1277 Flendrich
1278* Typo fix for GCC warning suppression. Harlan Stenn.
1279* Added tests/ntpd/ntp_scanner.c test. Damir Tomi��.
1280* Added declarations to all Unity tests, and did minor fixes to them.
1281 Reduced the number of warnings by half. Damir Tomi��.
1282* Updated generate_test_runner.rb and updated the sntp/unity/auto directory
1283 with the latest Unity updates from Mark. Damir Tomi��.
1284* Retire google test - phase I. Harlan Stenn.
1285* Unity test cleanup: move declaration of 'initializing'. Harlan Stenn.
1286* Update the NEWS file. Harlan Stenn.
1287* Autoconf cleanup. Harlan Stenn.
1288* Unit test dist cleanup. Harlan Stenn.
1289* Cleanup various test Makefile.am files. Harlan Stenn.
1290* Pthread autoconf macro cleanup. Harlan Stenn.
1291* Fix progname definition in unity runner scripts. Harlan Stenn.
1292* Clean trailing whitespace in tests/ntpd/Makefile.am. Harlan Stenn.
1293* Update the patch for bug 2817. Harlan Stenn.
1294* More updates for bug 2817. Harlan Stenn.
1295* Fix bugs in tests/ntpd/ntp_prio_q.c. Harlan Stenn.
1296* gcc on older HPUX may need +allowdups. Harlan Stenn.
1297* Adding missing MCAST protection. Harlan Stenn.
1298* Disable certain test programs on certain platforms. Harlan Stenn.
1299* Implement --enable-problem-tests (on by default). Harlan Stenn.
1300* build system tweaks. Harlan Stenn.
1301
1302---
1303NTP 4.2.8p3 (Harlan Stenn <stenn@ntp.org>, 2015/06/29)
1304
1305Focus: 1 Security fix. Bug fixes and enhancements. Leap-second improvements.
1306
1307Severity: MEDIUM
1308
1309Security Fix:
1310
1311* [Sec 2853] Crafted remote config packet can crash some versions of
1312 ntpd. Aleksis Kauppinen, Juergen Perlinger, Harlan Stenn.
1313
1314Under specific circumstances an attacker can send a crafted packet to
1315cause a vulnerable ntpd instance to crash. This requires each of the
1316following to be true:
1317
13181) ntpd set up to allow remote configuration (not allowed by default), and
13192) knowledge of the configuration password, and
13203) access to a computer entrusted to perform remote configuration.
1321
1322This vulnerability is considered low-risk.
1323
1324New features in this release:
1325
1326Optional (disabled by default) support to have ntpd provide smeared
1327leap second time. A specially built and configured ntpd will only
1328offer smeared time in response to client packets. These response
1329packets will also contain a "refid" of 254.a.b.c, where the 24 bits
1330of a, b, and c encode the amount of smear in a 2:22 integer:fraction
1331format. See README.leapsmear and http://bugs.ntp.org/2855 for more
1332information.
1333
1334 *IF YOU CHOOSE TO CONFIGURE NTPD TO PROVIDE LEAP SMEAR TIME*
1335 *BE SURE YOU DO NOT OFFER THAT TIME ON PUBLIC TIMESERVERS.*
1336
1337We've imported the Unity test framework, and have begun converting
1338the existing google-test items to this new framework. If you want
1339to write new tests or change old ones, you'll need to have ruby
1340installed. You don't need ruby to run the test suite.
1341
1342Bug Fixes and Improvements:
1343
1344* CID 739725: Fix a rare resource leak in libevent/listener.c.
1345* CID 1295478: Quiet a pedantic potential error from the fix for Bug 2776.
1346* CID 1296235: Fix refclock_jjy.c and correcting type of the driver40-ja.html
1347* CID 1269537: Clean up a line of dead code in getShmTime().
1348* [Bug 1060] Buffer overruns in libparse/clk_rawdcf.c. Helge Oldach.
1349* [Bug 2590] autogen-5.18.5.
1350* [Bug 2612] restrict: Warn when 'monitor' can't be disabled because
1351 of 'limited'.
1352* [Bug 2650] fix includefile processing.
1353* [Bug 2745] ntpd -x steps clock on leap second
1354 Fixed an initial-value problem that caused misbehaviour in absence of
1355 any leapsecond information.
1356 Do leap second stepping only of the step adjustment is beyond the
1357 proper jump distance limit and step correction is allowed at all.
1358* [Bug 2750] build for Win64
1359 Building for 32bit of loopback ppsapi needs def file
1360* [Bug 2776] Improve ntpq's 'help keytype'.
1361* [Bug 2778] Implement "apeers" ntpq command to include associd.
1362* [Bug 2782] Refactor refclock_shm.c, add memory barrier protection.
1363* [Bug 2792] If the IFF_RUNNING interface flag is supported then an
1364 interface is ignored as long as this flag is not set since the
1365 interface is not usable (e.g., no link).
1366* [Bug 2794] Clean up kernel clock status reports.
1367* [Bug 2800] refclock_true.c true_debug() can't open debug log because
1368 of incompatible open/fdopen parameters.
1369* [Bug 2804] install-local-data assumes GNU 'find' semantics.
1370* [Bug 2805] ntpd fails to join multicast group.
1371* [Bug 2806] refclock_jjy.c supports the Telephone JJY.
1372* [Bug 2808] GPSD_JSON driver enhancements, step 1.
1373 Fix crash during cleanup if GPS device not present and char device.
1374 Increase internal token buffer to parse all JSON data, even SKY.
1375 Defer logging of errors during driver init until the first unit is
1376 started, so the syslog is not cluttered when the driver is not used.
1377 Various improvements, see http://bugs.ntp.org/2808 for details.
1378 Changed libjsmn to a more recent version.
1379* [Bug 2810] refclock_shm.c memory barrier code needs tweaks for QNX.
1380* [Bug 2813] HP-UX needs -D__STDC_VERSION__=199901L and limits.h.
1381* [Bug 2815] net-snmp before v5.4 has circular library dependencies.
1382* [Bug 2821] Add a missing NTP_PRINTF and a missing const.
1383* [Bug 2822] New leap column in sntp broke NTP::Util.pm.
1384* [Bug 2824] Convert update-leap to perl. (also see 2769)
1385* [Bug 2825] Quiet file installation in html/ .
1386* [Bug 2830] ntpd doesn't always transfer the correct TAI offset via autokey
1387 NTPD transfers the current TAI (instead of an announcement) now.
1388 This might still needed improvement.
1389 Update autokey data ASAP when 'sys_tai' changes.
1390 Fix unit test that was broken by changes for autokey update.
1391 Avoid potential signature length issue and use DPRINTF where possible
1392 in ntp_crypto.c.
1393* [Bug 2832] refclock_jjy.c supports the TDC-300.
1394* [Bug 2834] Correct a broken html tag in html/refclock.html
1395* [Bug 2836] DFC77 patches from Frank Kardel to make decoding more
1396 robust, and require 2 consecutive timestamps to be consistent.
1397* [Bug 2837] Allow a configurable DSCP value.
1398* [Bug 2837] add test for DSCP to ntpd/complete.conf.in
1399* [Bug 2842] Glitch in ntp.conf.def documentation stanza.
1400* [Bug 2842] Bug in mdoc2man.
1401* [Bug 2843] make check fails on 4.3.36
1402 Fixed compiler warnings about numeric range overflow
1403 (The original topic was fixed in a byplay to bug#2830)
1404* [Bug 2845] Harden memory allocation in ntpd.
1405* [Bug 2852] 'make check' can't find unity.h. Hal Murray.
1406* [Bug 2854] Missing brace in libntp/strdup.c. Masanari Iida.
1407* [Bug 2855] Parser fix for conditional leap smear code. Harlan Stenn.
1408* [Bug 2855] Report leap smear in the REFID. Harlan Stenn.
1409* [Bug 2855] Implement conditional leap smear code. Martin Burnicki.
1410* [Bug 2856] ntpd should wait() on terminated child processes. Paul Green.
1411* [Bug 2857] Stratus VOS does not support SIGIO. Paul Green.
1412* [Bug 2859] Improve raw DCF77 robustness deconding. Frank Kardel.
1413* [Bug 2860] ntpq ifstats sanity check is too stringent. Frank Kardel.
1414* html/drivers/driver22.html: typo fix. Harlan Stenn.
1415* refidsmear test cleanup. Tomasz Flendrich.
1416* refidsmear function support and tests. Harlan Stenn.
1417* sntp/tests/Makefile.am: remove g_nameresolution.cpp as it tested
1418 something that was only in the 4.2.6 sntp. Harlan Stenn.
1419* Modified tests/bug-2803/Makefile.am so it builds Unity framework tests.
1420 Damir Tomi��
1421* Modified tests/libtnp/Makefile.am so it builds Unity framework tests.
1422 Damir Tomi��
1423* Modified sntp/tests/Makefile.am so it builds Unity framework tests.
1424 Damir Tomi��
1425* tests/sandbox/smeartest.c: Harlan Stenn, Damir Tomic, Juergen Perlinger.
1426* Converted from gtest to Unity: tests/bug-2803/. Damir Tomi��
1427* Converted from gtest to Unity: tests/libntp/ a_md5encrypt, atoint.c,
1428 atouint.c, authkeys.c, buftvtots.c, calendar.c, caljulian.c,
1429 calyearstart.c, clocktime.c, hextoint.c, lfpfunc.c, modetoa.c,
1430 numtoa.c, numtohost.c, refnumtoa.c, ssl_init.c, statestr.c,
1431 timespecops.c, timevalops.c, uglydate.c, vi64ops.c, ymd2yd.c.
1432 Damir Tomi��
1433* Converted from gtest to Unity: sntp/tests/ kodDatabase.c, kodFile.c,
1434 networking.c, keyFile.c, utilities.cpp, sntptest.h,
1435 fileHandlingTest.h. Damir Tomi��
1436* Initial support for experimental leap smear code. Harlan Stenn.
1437* Fixes to sntp/tests/fileHandlingTest.h.in. Harlan Stenn.
1438* Report select() debug messages at debug level 3 now.
1439* sntp/scripts/genLocInfo: treat raspbian as debian.
1440* Unity test framework fixes.
1441 ** Requires ruby for changes to tests.
1442* Initial support for PACKAGE_VERSION tests.
1443* sntp/libpkgver belongs in EXTRA_DIST, not DIST_SUBDIRS.
1444* tests/bug-2803/Makefile.am must distribute bug-2803.h.
1445* Add an assert to the ntpq ifstats code.
1446* Clean up the RLIMIT_STACK code.
1447* Improve the ntpq documentation around the controlkey keyid.
1448* ntpq.c cleanup.
1449* Windows port build cleanup.
1450
1451---
1452NTP 4.2.8p2 (Harlan Stenn <stenn@ntp.org>, 2015/04/07)
1453
1454Focus: Security and Bug fixes, enhancements.
1455
1456Severity: MEDIUM
1457
1458In addition to bug fixes and enhancements, this release fixes the
1459following medium-severity vulnerabilities involving private key
1460authentication:
1461
1462* [Sec 2779] ntpd accepts unauthenticated packets with symmetric key crypto.
1463
1464 References: Sec 2779 / CVE-2015-1798 / VU#374268
1465 Affects: All NTP4 releases starting with ntp-4.2.5p99 up to but not
1466 including ntp-4.2.8p2 where the installation uses symmetric keys
1467 to authenticate remote associations.
1468 CVSS: (AV:A/AC:M/Au:N/C:P/I:P/A:P) Base Score: 5.4
1469 Date Resolved: Stable (4.2.8p2) 07 Apr 2015
1470 Summary: When ntpd is configured to use a symmetric key to authenticate
1471 a remote NTP server/peer, it checks if the NTP message
1472 authentication code (MAC) in received packets is valid, but not if
1473 there actually is any MAC included. Packets without a MAC are
1474 accepted as if they had a valid MAC. This allows a MITM attacker to
1475 send false packets that are accepted by the client/peer without
1476 having to know the symmetric key. The attacker needs to know the
1477 transmit timestamp of the client to match it in the forged reply
1478 and the false reply needs to reach the client before the genuine
1479 reply from the server. The attacker doesn't necessarily need to be
1480 relaying the packets between the client and the server.
1481
1482 Authentication using autokey doesn't have this problem as there is
1483 a check that requires the key ID to be larger than NTP_MAXKEY,
1484 which fails for packets without a MAC.
1485 Mitigation:
1486 Upgrade to 4.2.8p2, or later, from the NTP Project Download Page
1487 or the NTP Public Services Project Download Page
1488 Configure ntpd with enough time sources and monitor it properly.
1489 Credit: This issue was discovered by Miroslav Lichvar, of Red Hat.
1490
1491* [Sec 2781] Authentication doesn't protect symmetric associations against
1492 DoS attacks.
1493
1494 References: Sec 2781 / CVE-2015-1799 / VU#374268
1495 Affects: All NTP releases starting with at least xntp3.3wy up to but
1496 not including ntp-4.2.8p2 where the installation uses symmetric
1497 key authentication.
1498 CVSS: (AV:A/AC:M/Au:N/C:P/I:P/A:P) Base Score: 5.4
1499 Note: the CVSS base Score for this issue could be 4.3 or lower, and
1500 it could be higher than 5.4.
1501 Date Resolved: Stable (4.2.8p2) 07 Apr 2015
1502 Summary: An attacker knowing that NTP hosts A and B are peering with
1503 each other (symmetric association) can send a packet to host A
1504 with source address of B which will set the NTP state variables
1505 on A to the values sent by the attacker. Host A will then send
1506 on its next poll to B a packet with originate timestamp that
1507 doesn't match the transmit timestamp of B and the packet will
1508 be dropped. If the attacker does this periodically for both
1509 hosts, they won't be able to synchronize to each other. This is
1510 a known denial-of-service attack, described at
1511 https://www.eecis.udel.edu/~mills/onwire.html .
1512
1513 According to the document the NTP authentication is supposed to
1514 protect symmetric associations against this attack, but that
1515 doesn't seem to be the case. The state variables are updated even
1516 when authentication fails and the peers are sending packets with
1517 originate timestamps that don't match the transmit timestamps on
1518 the receiving side.
1519
1520 This seems to be a very old problem, dating back to at least
1521 xntp3.3wy. It's also in the NTPv3 (RFC 1305) and NTPv4 (RFC 5905)
1522 specifications, so other NTP implementations with support for
1523 symmetric associations and authentication may be vulnerable too.
1524 An update to the NTP RFC to correct this error is in-process.
1525 Mitigation:
1526 Upgrade to 4.2.8p2, or later, from the NTP Project Download Page
1527 or the NTP Public Services Project Download Page
1528 Note that for users of autokey, this specific style of MITM attack
1529 is simply a long-known potential problem.
1530 Configure ntpd with appropriate time sources and monitor ntpd.
1531 Alert your staff if problems are detected.
1532 Credit: This issue was discovered by Miroslav Lichvar, of Red Hat.
1533
1534* New script: update-leap
1535The update-leap script will verify and if necessary, update the
1536leap-second definition file.
1537It requires the following commands in order to work:
1538
1539 wget logger tr sed shasum
1540
1541Some may choose to run this from cron. It needs more portability testing.
1542
1543Bug Fixes and Improvements:
1544
1545* [Bug 1787] DCF77's formerly "antenna" bit is "call bit" since 2003.
1546* [Bug 1960] setsockopt IPV6_MULTICAST_IF: Invalid argument.
1547* [Bug 2346] "graceful termination" signals do not do peer cleanup.
1548* [Bug 2728] See if C99-style structure initialization works.
1549* [Bug 2747] Upgrade libevent to 2.1.5-beta.
1550* [Bug 2749] ntp/lib/NTP/Util.pm needs update for ntpq -w, IPv6, .POOL. .
1551* [Bug 2751] jitter.h has stale copies of l_fp macros.
1552* [Bug 2756] ntpd hangs in startup with gcc 3.3.5 on ARM.
1553* [Bug 2757] Quiet compiler warnings.
1554* [Bug 2759] Expose nonvolatile/clk_wander_threshold to ntpq.
1555* [Bug 2763] Allow different thresholds for forward and backward steps.
1556* [Bug 2766] ntp-keygen output files should not be world-readable.
1557* [Bug 2767] ntp-keygen -M should symlink to ntp.keys.
1558* [Bug 2771] nonvolatile value is documented in wrong units.
1559* [Bug 2773] Early leap announcement from Palisade/Thunderbolt
1560* [Bug 2774] Unreasonably verbose printout - leap pending/warning
1561* [Bug 2775] ntp-keygen.c fails to compile under Windows.
1562* [Bug 2777] Fixed loops and decoding of Meinberg GPS satellite info.
1563 Removed non-ASCII characters from some copyright comments.
1564 Removed trailing whitespace.
1565 Updated definitions for Meinberg clocks from current Meinberg header files.
1566 Now use C99 fixed-width types and avoid non-ASCII characters in comments.
1567 Account for updated definitions pulled from Meinberg header files.
1568 Updated comments on Meinberg GPS receivers which are not only called GPS16x.
1569 Replaced some constant numbers by defines from ntp_calendar.h
1570 Modified creation of parse-specific variables for Meinberg devices
1571 in gps16x_message().
1572 Reworked mk_utcinfo() to avoid printing of ambiguous leap second dates.
1573 Modified mbg_tm_str() which now expexts an additional parameter controlling
1574 if the time status shall be printed.
1575* [Sec 2779] ntpd accepts unauthenticated packets with symmetric key crypto.
1576* [Sec 2781] Authentication doesn't protect symmetric associations against
1577 DoS attacks.
1578* [Bug 2783] Quiet autoconf warnings about missing AC_LANG_SOURCE.
1579* [Bug 2789] Quiet compiler warnings from libevent.
1580* [Bug 2790] If ntpd sets the Windows MM timer highest resolution
1581 pause briefly before measuring system clock precision to yield
1582 correct results.
1583* Comment from Juergen Perlinger in ntp_calendar.c to make the code clearer.
1584* Use predefined function types for parse driver functions
1585 used to set up function pointers.
1586 Account for changed prototype of parse_inp_fnc_t functions.
1587 Cast parse conversion results to appropriate types to avoid
1588 compiler warnings.
1589 Let ioctl() for Windows accept a (void *) to avoid compiler warnings
1590 when called with pointers to different types.
1591
1592---
1593NTP 4.2.8p1 (Harlan Stenn <stenn@ntp.org>, 2015/02/04)
1594
1595Focus: Security and Bug fixes, enhancements.
1596
1597Severity: HIGH
1598
1599In addition to bug fixes and enhancements, this release fixes the
1600following high-severity vulnerabilities:
1601
1602* vallen is not validated in several places in ntp_crypto.c, leading
1603 to a potential information leak or possibly a crash
1604
1605 References: Sec 2671 / CVE-2014-9297 / VU#852879
1606 Affects: All NTP4 releases before 4.2.8p1 that are running autokey.
1607 CVSS: (AV:N/AC:L/Au:N/C:P/I:P/A:P) Base Score: 7.5
1608 Date Resolved: Stable (4.2.8p1) 04 Feb 2015
1609 Summary: The vallen packet value is not validated in several code
1610 paths in ntp_crypto.c which can lead to information leakage
1611 or perhaps a crash of the ntpd process.
1612 Mitigation - any of:
1613 Upgrade to 4.2.8p1, or later, from the NTP Project Download Page
1614 or the NTP Public Services Project Download Page.
1615 Disable Autokey Authentication by removing, or commenting out,
1616 all configuration directives beginning with the "crypto"
1617 keyword in your ntp.conf file.
1618 Credit: This vulnerability was discovered by Stephen Roettger of the
1619 Google Security Team, with additional cases found by Sebastian
1620 Krahmer of the SUSE Security Team and Harlan Stenn of Network
1621 Time Foundation.
1622
1623* ::1 can be spoofed on some OSes, so ACLs based on IPv6 ::1 addresses
1624 can be bypassed.
1625
1626 References: Sec 2672 / CVE-2014-9298 / VU#852879
1627 Affects: All NTP4 releases before 4.2.8p1, under at least some
1628 versions of MacOS and Linux. *BSD has not been seen to be vulnerable.
1629 CVSS: (AV:N/AC:L/Au:N/C:P/I:P/A:C) Base Score: 9
1630 Date Resolved: Stable (4.2.8p1) 04 Feb 2014
1631 Summary: While available kernels will prevent 127.0.0.1 addresses
1632 from "appearing" on non-localhost IPv4 interfaces, some kernels
1633 do not offer the same protection for ::1 source addresses on
1634 IPv6 interfaces. Since NTP's access control is based on source
1635 address and localhost addresses generally have no restrictions,
1636 an attacker can send malicious control and configuration packets
1637 by spoofing ::1 addresses from the outside. Note Well: This is
1638 not really a bug in NTP, it's a problem with some OSes. If you
1639 have one of these OSes where ::1 can be spoofed, ALL ::1 -based
1640 ACL restrictions on any application can be bypassed!
1641 Mitigation:
1642 Upgrade to 4.2.8p1, or later, from the NTP Project Download Page
1643 or the NTP Public Services Project Download Page
1644 Install firewall rules to block packets claiming to come from
1645 ::1 from inappropriate network interfaces.
1646 Credit: This vulnerability was discovered by Stephen Roettger of
1647 the Google Security Team.
1648
1649Additionally, over 30 bugfixes and improvements were made to the codebase.
1650See the ChangeLog for more information.
1651
1652---
1653NTP 4.2.8 (Harlan Stenn <stenn@ntp.org>, 2014/12/18)
1654
1655Focus: Security and Bug fixes, enhancements.
1656
1657Severity: HIGH
1658
1659In addition to bug fixes and enhancements, this release fixes the
1660following high-severity vulnerabilities:
1661
1662************************** vv NOTE WELL vv *****************************
1663
1664The vulnerabilities listed below can be significantly mitigated by
1665following the BCP of putting
1666
1667 restrict default ... noquery
1668
1669in the ntp.conf file. With the exception of:
1670
1671 receive(): missing return on error
1672 References: Sec 2670 / CVE-2014-9296 / VU#852879
1673
1674below (which is a limited-risk vulnerability), none of the recent
1675vulnerabilities listed below can be exploited if the source IP is
1676restricted from sending a 'query'-class packet by your ntp.conf file.
1677
1678************************** ^^ NOTE WELL ^^ *****************************
1679
1680* Weak default key in config_auth().
1681
1682 References: [Sec 2665] / CVE-2014-9293 / VU#852879
1683 CVSS: (AV:N/AC:L/Au:M/C:P/I:P/A:C) Base Score: 7.3
1684 Vulnerable Versions: all releases prior to 4.2.7p11
1685 Date Resolved: 28 Jan 2010
1686
1687 Summary: If no 'auth' key is set in the configuration file, ntpd
1688 would generate a random key on the fly. There were two
1689 problems with this: 1) the generated key was 31 bits in size,
1690 and 2) it used the (now weak) ntp_random() function, which was
1691 seeded with a 32-bit value and could only provide 32 bits of
1692 entropy. This was sufficient back in the late 1990s when the
1693 code was written. Not today.
1694
1695 Mitigation - any of:
1696 - Upgrade to 4.2.7p11 or later.
1697 - Follow BCP and put 'restrict ... noquery' in your ntp.conf file.
1698
1699 Credit: This vulnerability was noticed in ntp-4.2.6 by Neel Mehta
1700 of the Google Security Team.
1701
1702* Non-cryptographic random number generator with weak seed used by
1703 ntp-keygen to generate symmetric keys.
1704
1705 References: [Sec 2666] / CVE-2014-9294 / VU#852879
1706 CVSS: (AV:N/AC:L/Au:M/C:P/I:P/A:C) Base Score: 7.3
1707 Vulnerable Versions: All NTP4 releases before 4.2.7p230
1708 Date Resolved: Dev (4.2.7p230) 01 Nov 2011
1709
1710 Summary: Prior to ntp-4.2.7p230 ntp-keygen used a weak seed to
1711 prepare a random number generator that was of good quality back
1712 in the late 1990s. The random numbers produced was then used to
1713 generate symmetric keys. In ntp-4.2.8 we use a current-technology
1714 cryptographic random number generator, either RAND_bytes from
1715 OpenSSL, or arc4random().
1716
1717 Mitigation - any of:
1718 - Upgrade to 4.2.7p230 or later.
1719 - Follow BCP and put 'restrict ... noquery' in your ntp.conf file.
1720
1721 Credit: This vulnerability was discovered in ntp-4.2.6 by
1722 Stephen Roettger of the Google Security Team.
1723
1724* Buffer overflow in crypto_recv()
1725
1726 References: Sec 2667 / CVE-2014-9295 / VU#852879
1727 CVSS: (AV:N/AC:L/Au:N/C:P/I:P/A:P) Base Score: 7.5
1728 Versions: All releases before 4.2.8
1729 Date Resolved: Stable (4.2.8) 18 Dec 2014
1730
1731 Summary: When Autokey Authentication is enabled (i.e. the ntp.conf
1732 file contains a 'crypto pw ...' directive) a remote attacker
1733 can send a carefully crafted packet that can overflow a stack
1734 buffer and potentially allow malicious code to be executed
1735 with the privilege level of the ntpd process.
1736
1737 Mitigation - any of:
1738 - Upgrade to 4.2.8, or later, or
1739 - Disable Autokey Authentication by removing, or commenting out,
1740 all configuration directives beginning with the crypto keyword
1741 in your ntp.conf file.
1742
1743 Credit: This vulnerability was discovered by Stephen Roettger of the
1744 Google Security Team.
1745
1746* Buffer overflow in ctl_putdata()
1747
1748 References: Sec 2668 / CVE-2014-9295 / VU#852879
1749 CVSS: (AV:N/AC:L/Au:N/C:P/I:P/A:P) Base Score: 7.5
1750 Versions: All NTP4 releases before 4.2.8
1751 Date Resolved: Stable (4.2.8) 18 Dec 2014
1752
1753 Summary: A remote attacker can send a carefully crafted packet that
1754 can overflow a stack buffer and potentially allow malicious
1755 code to be executed with the privilege level of the ntpd process.
1756
1757 Mitigation - any of:
1758 - Upgrade to 4.2.8, or later.
1759 - Follow BCP and put 'restrict ... noquery' in your ntp.conf file.
1760
1761 Credit: This vulnerability was discovered by Stephen Roettger of the
1762 Google Security Team.
1763
1764* Buffer overflow in configure()
1765
1766 References: Sec 2669 / CVE-2014-9295 / VU#852879
1767 CVSS: (AV:N/AC:L/Au:N/C:P/I:P/A:P) Base Score: 7.5
1768 Versions: All NTP4 releases before 4.2.8
1769 Date Resolved: Stable (4.2.8) 18 Dec 2014
1770
1771 Summary: A remote attacker can send a carefully crafted packet that
1772 can overflow a stack buffer and potentially allow malicious
1773 code to be executed with the privilege level of the ntpd process.
1774
1775 Mitigation - any of:
1776 - Upgrade to 4.2.8, or later.
1777 - Follow BCP and put 'restrict ... noquery' in your ntp.conf file.
1778
1779 Credit: This vulnerability was discovered by Stephen Roettger of the
1780 Google Security Team.
1781
1782* receive(): missing return on error
1783
1784 References: Sec 2670 / CVE-2014-9296 / VU#852879
1785 CVSS: (AV:N/AC:L/Au:N/C:N/I:N/A:P) Base Score: 5.0
1786 Versions: All NTP4 releases before 4.2.8
1787 Date Resolved: Stable (4.2.8) 18 Dec 2014
1788
1789 Summary: Code in ntp_proto.c:receive() was missing a 'return;' in
1790 the code path where an error was detected, which meant
1791 processing did not stop when a specific rare error occurred.
1792 We haven't found a way for this bug to affect system integrity.
1793 If there is no way to affect system integrity the base CVSS
1794 score for this bug is 0. If there is one avenue through which
1795 system integrity can be partially affected, the base score
1796 becomes a 5. If system integrity can be partially affected
1797 via all three integrity metrics, the CVSS base score become 7.5.
1798
1799 Mitigation - any of:
1800 - Upgrade to 4.2.8, or later,
1801 - Remove or comment out all configuration directives
1802 beginning with the crypto keyword in your ntp.conf file.
1803
1804 Credit: This vulnerability was discovered by Stephen Roettger of the
1805 Google Security Team.
1806
1807See http://support.ntp.org/security for more information.
1808
1809New features / changes in this release:
1810
1811Important Changes
1812
1813* Internal NTP Era counters
1814
1815The internal counters that track the "era" (range of years) we are in
1816rolls over every 136 years'. The current "era" started at the stroke of
1817midnight on 1 Jan 1900, and ends just before the stroke of midnight on
18181 Jan 2036.
1819In the past, we have used the "midpoint" of the range to decide which
1820era we were in. Given the longevity of some products, it became clear
1821that it would be more functional to "look back" less, and "look forward"
1822more. We now compile a timestamp into the ntpd executable and when we
1823get a timestamp we us the "built-on" to tell us what era we are in.
1824This check "looks back" 10 years, and "looks forward" 126 years.
1825
1826* ntpdc responses disabled by default
1827
1828Dave Hart writes:
1829
1830For a long time, ntpq and its mostly text-based mode 6 (control)
1831protocol have been preferred over ntpdc and its mode 7 (private
1832request) protocol for runtime queries and configuration. There has
1833been a goal of deprecating ntpdc, previously held back by numerous
1834capabilities exposed by ntpdc with no ntpq equivalent. I have been
1835adding commands to ntpq to cover these cases, and I believe I've
1836covered them all, though I've not compared command-by-command
1837recently.
1838
1839As I've said previously, the binary mode 7 protocol involves a lot of
1840hand-rolled structure layout and byte-swapping code in both ntpd and
1841ntpdc which is hard to get right. As ntpd grows and changes, the
1842changes are difficult to expose via ntpdc while maintaining forward
1843and backward compatibility between ntpdc and ntpd. In contrast,
1844ntpq's text-based, label=value approach involves more code reuse and
1845allows compatible changes without extra work in most cases.
1846
1847Mode 7 has always been defined as vendor/implementation-specific while
1848mode 6 is described in RFC 1305 and intended to be open to interoperate
1849with other implementations. There is an early draft of an updated
1850mode 6 description that likely will join the other NTPv4 RFCs
1851eventually. (http://tools.ietf.org/html/draft-odonoghue-ntpv4-control-01)
1852
1853For these reasons, ntpd 4.2.7p230 by default disables processing of
1854ntpdc queries, reducing ntpd's attack surface and functionally
1855deprecating ntpdc. If you are in the habit of using ntpdc for certain
1856operations, please try the ntpq equivalent. If there's no equivalent,
1857please open a bug report at http://bugs.ntp.org./
1858
1859In addition to the above, over 1100 issues have been resolved between
1860the 4.2.6 branch and 4.2.8. The ChangeLog file in the distribution
1861lists these.
1862
1863---
1864NTP 4.2.6p5 (Harlan Stenn <stenn@ntp.org>, 2011/12/24)
1865
1866Focus: Bug fixes
1867
1868Severity: Medium
1869
1870This is a recommended upgrade.
1871
1872This release updates sys_rootdisp and sys_jitter calculations to match the
1873RFC specification, fixes a potential IPv6 address matching error for the
1874"nic" and "interface" configuration directives, suppresses the creation of
1875extraneous ephemeral associations for certain broadcastclient and
1876multicastclient configurations, cleans up some ntpq display issues, and
1877includes improvements to orphan mode, minor bugs fixes and code clean-ups.
1878
1879New features / changes in this release:
1880
1881ntpd
1882
1883 * Updated "nic" and "interface" IPv6 address handling to prevent
1884 mismatches with localhost [::1] and wildcard [::] which resulted from
1885 using the address/prefix format (e.g. fe80::/64)
1886 * Fix orphan mode stratum incorrectly counting to infinity
1887 * Orphan parent selection metric updated to includes missing ntohl()
1888 * Non-printable stratum 16 refid no longer sent to ntp
1889 * Duplicate ephemeral associations suppressed for broadcastclient and
1890 multicastclient without broadcastdelay
1891 * Exclude undetermined sys_refid from use in loopback TEST12
1892 * Exclude MODE_SERVER responses from KoD rate limiting
1893 * Include root delay in clock_update() sys_rootdisp calculations
1894 * get_systime() updated to exclude sys_residual offset (which only
1895 affected bits "below" sys_tick, the precision threshold)
1896 * sys.peer jitter weighting corrected in sys_jitter calculation
1897
1898ntpq
1899
1900 * -n option extended to include the billboard "server" column
1901 * IPv6 addresses in the local column truncated to prevent overruns
1902
1903---
1904NTP 4.2.6p4 (Harlan Stenn <stenn@ntp.org>, 2011/09/22)
1905
1906Focus: Bug fixes and portability improvements
1907
1908Severity: Medium
1909
1910This is a recommended upgrade.
1911
1912This release includes build infrastructure updates, code
1913clean-ups, minor bug fixes, fixes for a number of minor
1914ref-clock issues, and documentation revisions.
1915
1916Portability improvements affect AIX, HP-UX, Linux, OS X and 64-bit time_t.
1917
1918New features / changes in this release:
1919
1920Build system
1921
1922* Fix checking for struct rtattr
1923* Update config.guess and config.sub for AIX
1924* Upgrade required version of autogen and libopts for building
1925 from our source code repository
1926
1927ntpd
1928
1929* Back-ported several fixes for Coverity warnings from ntp-dev
1930* Fix a rare boundary condition in UNLINK_EXPR_SLIST()
1931* Allow "logconfig =allall" configuration directive
1932* Bind tentative IPv6 addresses on Linux
1933* Correct WWVB/Spectracom driver to timestamp CR instead of LF
1934* Improved tally bit handling to prevent incorrect ntpq peer status reports
1935* Exclude the Undisciplined Local Clock and ACTS drivers from the initial
1936 candidate list unless they are designated a "prefer peer"
1937* Prevent the consideration of Undisciplined Local Clock or ACTS drivers for
1938 selection during the 'tos orphanwait' period
1939* Prefer an Orphan Mode Parent over the Undisciplined Local Clock or ACTS
1940 drivers
1941* Improved support of the Parse Refclock trusttime flag in Meinberg mode
1942* Back-port utility routines from ntp-dev: mprintf(), emalloc_zero()
1943* Added the NTPD_TICKADJ_PPM environment variable for specifying baseline
1944 clock slew on Microsoft Windows
1945* Code cleanup in libntpq
1946
1947ntpdc
1948
1949* Fix timerstats reporting
1950
1951ntpdate
1952
1953* Reduce time required to set clock
1954* Allow a timeout greater than 2 seconds
1955
1956sntp
1957
1958* Backward incompatible command-line option change:
1959 -l/--filelog changed -l/--logfile (to be consistent with ntpd)
1960
1961Documentation
1962
1963* Update html2man. Fix some tags in the .html files
1964* Distribute ntp-wait.html
1965
1966---
1967NTP 4.2.6p3 (Harlan Stenn <stenn@ntp.org>, 2011/01/03)
1968
1969Focus: Bug fixes and portability improvements
1970
1971Severity: Medium
1972
1973This is a recommended upgrade.
1974
1975This release includes build infrastructure updates, code
1976clean-ups, minor bug fixes, fixes for a number of minor
1977ref-clock issues, and documentation revisions.
1978
1979Portability improvements in this release affect AIX, Atari FreeMiNT,
1980FreeBSD4, Linux and Microsoft Windows.
1981
1982New features / changes in this release:
1983
1984Build system
1985* Use lsb_release to get information about Linux distributions.
1986* 'test' is in /usr/bin (instead of /bin) on some systems.
1987* Basic sanity checks for the ChangeLog file.
1988* Source certain build files with ./filename for systems without . in PATH.
1989* IRIX portability fix.
1990* Use a single copy of the "libopts" code.
1991* autogen/libopts upgrade.
1992* configure.ac m4 quoting cleanup.
1993
1994ntpd
1995* Do not bind to IN6_IFF_ANYCAST addresses.
1996* Log the reason for exiting under Windows.
1997* Multicast fixes for Windows.
1998* Interpolation fixes for Windows.
1999* IPv4 and IPv6 Multicast fixes.
2000* Manycast solicitation fixes and general repairs.
2001* JJY refclock cleanup.
2002* NMEA refclock improvements.
2003* Oncore debug message cleanup.
2004* Palisade refclock now builds under Linux.
2005* Give RAWDCF more baud rates.
2006* Support Truetime Satellite clocks under Windows.
2007* Support Arbiter 1093C Satellite clocks under Windows.
2008* Make sure that the "filegen" configuration command defaults to "enable".
2009* Range-check the status codes (plus other cleanup) in the RIPE-NCC driver.
2010* Prohibit 'includefile' directive in remote configuration command.
2011* Fix 'nic' interface bindings.
2012* Fix the way we link with openssl if openssl is installed in the base
2013 system.
2014
2015ntp-keygen
2016* Fix -V coredump.
2017* OpenSSL version display cleanup.
2018
2019ntpdc
2020* Many counters should be treated as unsigned.
2021
2022ntpdate
2023* Do not ignore replies with equal receive and transmit timestamps.
2024
2025ntpq
2026* libntpq warning cleanup.
2027
2028ntpsnmpd
2029* Correct SNMP type for "precision" and "resolution".
2030* Update the MIB from the draft version to RFC-5907.
2031
2032sntp
2033* Display timezone offset when showing time for sntp in the local
2034 timezone.
2035* Pay proper attention to RATE KoD packets.
2036* Fix a miscalculation of the offset.
2037* Properly parse empty lines in the key file.
2038* Logging cleanup.
2039* Use tv_usec correctly in set_time().
2040* Documentation cleanup.
2041
2042---
2043NTP 4.2.6p2 (Harlan Stenn <stenn@ntp.org>, 2010/07/08)
2044
2045Focus: Bug fixes and portability improvements
2046
2047Severity: Medium
2048
2049This is a recommended upgrade.
2050
2051This release includes build infrastructure updates, code
2052clean-ups, minor bug fixes, fixes for a number of minor
2053ref-clock issues, improved KOD handling, OpenSSL related
2054updates and documentation revisions.
2055
2056Portability improvements in this release affect Irix, Linux,
2057Mac OS, Microsoft Windows, OpenBSD and QNX6
2058
2059New features / changes in this release:
2060
2061ntpd
2062* Range syntax for the trustedkey configuration directive
2063* Unified IPv4 and IPv6 restrict lists
2064
2065ntpdate
2066* Rate limiting and KOD handling
2067
2068ntpsnmpd
2069* default connection to net-snmpd via a unix-domain socket
2070* command-line 'socket name' option
2071
2072ntpq / ntpdc
2073* support for the "passwd ..." syntax
2074* key-type specific password prompts
2075
2076sntp
2077* MD5 authentication of an ntpd
2078* Broadcast and crypto
2079* OpenSSL support
2080
2081---
2082NTP 4.2.6p1 (Harlan Stenn <stenn@ntp.org>, 2010/04/09)
2083
2084Focus: Bug fixes, portability fixes, and documentation improvements
2085
2086Severity: Medium
2087
2088This is a recommended upgrade.
2089
2090---
2091NTP 4.2.6 (Harlan Stenn <stenn@ntp.org>, 2009/12/08)
2092
2093Focus: enhancements and bug fixes.
2094
2095---
2096NTP 4.2.4p8 (Harlan Stenn <stenn@ntp.org>, 2009/12/08)
2097
2098Focus: Security Fixes
2099
2100Severity: HIGH
2101
2102This release fixes the following high-severity vulnerability:
2103
2104* [Sec 1331] DoS with mode 7 packets - CVE-2009-3563.
2105
2106 See http://support.ntp.org/security for more information.
2107
2108 NTP mode 7 (MODE_PRIVATE) is used by the ntpdc query and control utility.
2109 In contrast, ntpq uses NTP mode 6 (MODE_CONTROL), while routine NTP time
2110 transfers use modes 1 through 5. Upon receipt of an incorrect mode 7
2111 request or a mode 7 error response from an address which is not listed
2112 in a "restrict ... noquery" or "restrict ... ignore" statement, ntpd will
2113 reply with a mode 7 error response (and log a message). In this case:
2114
2115 * If an attacker spoofs the source address of ntpd host A in a
2116 mode 7 response packet sent to ntpd host B, both A and B will
2117 continuously send each other error responses, for as long as
2118 those packets get through.
2119
2120 * If an attacker spoofs an address of ntpd host A in a mode 7
2121 response packet sent to ntpd host A, A will respond to itself
2122 endlessly, consuming CPU and logging excessively.
2123
2124 Credit for finding this vulnerability goes to Robin Park and Dmitri
2125 Vinokurov of Alcatel-Lucent.
2126
2127THIS IS A STRONGLY RECOMMENDED UPGRADE.
2128
2129---
2130ntpd now syncs to refclocks right away.
2131
2132Backward-Incompatible changes:
2133
2134ntpd no longer accepts '-v name' or '-V name' to define internal variables.
2135Use '--var name' or '--dvar name' instead. (Bug 817)
2136
2137---
2138NTP 4.2.4p7 (Harlan Stenn <stenn@ntp.org>, 2009/05/04)
2139
2140Focus: Security and Bug Fixes
2141
2142Severity: HIGH
2143
2144This release fixes the following high-severity vulnerability:
2145
2146* [Sec 1151] Remote exploit if autokey is enabled. CVE-2009-1252
2147
2148 See http://support.ntp.org/security for more information.
2149
2150 If autokey is enabled (if ntp.conf contains a "crypto pw whatever"
2151 line) then a carefully crafted packet sent to the machine will cause
2152 a buffer overflow and possible execution of injected code, running
2153 with the privileges of the ntpd process (often root).
2154
2155 Credit for finding this vulnerability goes to Chris Ries of CMU.
2156
2157This release fixes the following low-severity vulnerabilities:
2158
2159* [Sec 1144] limited (two byte) buffer overflow in ntpq. CVE-2009-0159
2160 Credit for finding this vulnerability goes to Geoff Keating of Apple.
2161
2162* [Sec 1149] use SO_EXCLUSIVEADDRUSE on Windows
2163 Credit for finding this issue goes to Dave Hart.
2164
2165This release fixes a number of bugs and adds some improvements:
2166
2167* Improved logging
2168* Fix many compiler warnings
2169* Many fixes and improvements for Windows
2170* Adds support for AIX 6.1
2171* Resolves some issues under MacOS X and Solaris
2172
2173THIS IS A STRONGLY RECOMMENDED UPGRADE.
2174
2175---
2176NTP 4.2.4p6 (Harlan Stenn <stenn@ntp.org>, 2009/01/07)
2177
2178Focus: Security Fix
2179
2180Severity: Low
2181
2182This release fixes oCERT.org's CVE-2009-0021, a vulnerability affecting
2183the OpenSSL library relating to the incorrect checking of the return
2184value of EVP_VerifyFinal function.
2185
2186Credit for finding this issue goes to the Google Security Team for
2187finding the original issue with OpenSSL, and to ocert.org for finding
2188the problem in NTP and telling us about it.
2189
2190This is a recommended upgrade.
2191---
2192NTP 4.2.4p5 (Harlan Stenn <stenn@ntp.org>, 2008/08/17)
2193
2194Focus: Minor Bugfixes
2195
2196This release fixes a number of Windows-specific ntpd bugs and
2197platform-independent ntpdate bugs. A logging bugfix has been applied
2198to the ONCORE driver.
2199
2200The "dynamic" keyword and is now obsolete and deferred binding to local
2201interfaces is the new default. The minimum time restriction for the
2202interface update interval has been dropped.
2203
2204A number of minor build system and documentation fixes are included.
2205
2206This is a recommended upgrade for Windows.
2207
2208---
2209NTP 4.2.4p4 (Harlan Stenn <stenn@ntp.org>, 2007/09/10)
2210
2211Focus: Minor Bugfixes
2212
2213This release updates certain copyright information, fixes several display
2214bugs in ntpdc, avoids SIGIO interrupting malloc(), cleans up file descriptor
2215shutdown in the parse refclock driver, removes some lint from the code,
2216stops accessing certain buffers immediately after they were freed, fixes
2217a problem with non-command-line specification of -6, and allows the loopback
2218interface to share addresses with other interfaces.
2219
2220---
2221NTP 4.2.4p3 (Harlan Stenn <stenn@ntp.org>, 2007/06/29)
2222
2223Focus: Minor Bugfixes
2224
2225This release fixes a bug in Windows that made it difficult to
2226terminate ntpd under windows.
2227This is a recommended upgrade for Windows.
2228
2229---
2230NTP 4.2.4p2 (Harlan Stenn <stenn@ntp.org>, 2007/06/19)
2231
2232Focus: Minor Bugfixes
2233
2234This release fixes a multicast mode authentication problem,
2235an error in NTP packet handling on Windows that could lead to
2236ntpd crashing, and several other minor bugs. Handling of
2237multicast interfaces and logging configuration were improved.
2238The required versions of autogen and libopts were incremented.
2239This is a recommended upgrade for Windows and multicast users.
2240
2241---
2242NTP 4.2.4 (Harlan Stenn <stenn@ntp.org>, 2006/12/31)
2243
2244Focus: enhancements and bug fixes.
2245
2246Dynamic interface rescanning was added to simplify the use of ntpd in
2247conjunction with DHCP. GNU AutoGen is used for its command-line options
2248processing. Separate PPS devices are supported for PARSE refclocks, MD5
2249signatures are now provided for the release files. Drivers have been
2250added for some new ref-clocks and have been removed for some older
2251ref-clocks. This release also includes other improvements, documentation
2252and bug fixes.
2253
2254K&R C is no longer supported as of NTP-4.2.4. We are now aiming for ANSI
2255C support.
2256
2257---
2258NTP 4.2.0 (Harlan Stenn <stenn@ntp.org>, 2003/10/15)
2259
2260Focus: enhancements and bug fixes.