CVE-2015-7705

The rate limiting feature in NTP 4.x before 4.2.8p4 and 4.3.x before 4.3.77 allows remote attackers to have unspecified impact via a large number of crafted requests.

These are all security issues fixed in the ntp-4.2.8p9-1.1 package on the GA media of openSUSE Tumbleweed.

This ntp update provides the following security and non security fixes:

• Update to 4.2.8p4 to fix several security issues (bsc#951608):
  • CVE-2015-7871: NAK to the Future: Symmetric association authentication bypass via crypto-NAK
  • CVE-2015-7855: decodenetnum() will ASSERT botch instead of returning FAIL on some bogus values
  • CVE-2015-7854: Password Length Memory Corruption Vulnerability
  • CVE-2015-7853: Invalid length data provided by a custom refclock driver could cause a buffer overflow
  • CVE-2015-7852 ntpq atoascii() Memory Corruption Vulnerability
  • CVE-2015-7851 saveconfig Directory Traversal Vulnerability
  • CVE-2015-7850 remote config logfile-keyfile
  • CVE-2015-7849 trusted key use-after-free
  • CVE-2015-7848 mode 7 loop counter underrun
  • CVE-2015-7701 Slow memory leak in CRYPTO_ASSOC
  • CVE-2015-7703 configuration directives 'pidfile' and 'driftfile' should only be allowed locally
  • CVE-2015-7704, CVE-2015-7705 Clients that receive a KoD should validate the origin timestamp field
  • CVE-2015-7691, CVE-2015-7692, CVE-2015-7702 Incomplete autokey data packet length checks
• Use ntpq instead of deprecated ntpdc in start-ntpd (bnc#936327).
• Add a controlkey to ntp.conf to make the above work.
• Improve runtime configuration:
  • Read keytype from ntp.conf
  • Don't write ntp keys to syslog.
• Don't let 'keysdir' lines in ntp.conf trigger the 'keys' parser.
• Fix the comment regarding addserver in ntp.conf (bnc#910063).
• Remove ntp.1.gz, it wasn't installed anymore.
• Remove ntp-4.2.7-rh-manpages.tar.gz and only keep ntptime.8.gz. The rest is partially irrelevant, partially redundant and potentially outdated (bsc#942587).
• Remove 'kod' from the restrict line in ntp.conf (bsc#944300).
• Use SHA1 instead of MD5 for symmetric keys (bsc#905885).
• Require perl-Socket6 (bsc#942441).
• Fix incomplete backporting of 'rcntp ntptimemset'.

ntp was updated to version 4.2.8p6 to fix 28 security issues.

Major functional changes:

• The 'sntp' commandline tool changed its option handling in a major way, some options have been renamed or dropped.
• 'controlkey 1' is added during update to ntp.conf to allow sntp to work.
• The local clock is being disabled during update.
• ntpd is no longer running chrooted.

Other functional changes:

• ntp-signd is installed.
• 'enable mode7' can be added to the configuration to allow ntdpc to work as compatibility mode option.
• 'kod' was removed from the default restrictions.
• SHA1 keys are used by default instead of MD5 keys.

Also yast2-ntp-client was updated to match some sntp syntax changes. (bsc#937837)

These security issues were fixed:

• CVE-2015-8158: Fixed potential infinite loop in ntpq (bsc#962966).
• CVE-2015-8138: Zero Origin Timestamp Bypass (bsc#963002).
• CVE-2015-7979: Off-path Denial of Service (DoS) attack on authenticated broadcast mode (bsc#962784).
• CVE-2015-7978: Stack exhaustion in recursive traversal of restriction list (bsc#963000).
• CVE-2015-7977: reslist NULL pointer dereference (bsc#962970).
• CVE-2015-7976: ntpq saveconfig command allows dangerous characters in filenames (bsc#962802).
• CVE-2015-7975: nextvar() missing length check (bsc#962988).
• CVE-2015-7974: Skeleton Key: Missing key check allows impersonation between authenticated peers (bsc#962960).
• CVE-2015-7973: Replay attack on authenticated broadcast mode (bsc#962995).
• CVE-2015-8140: ntpq vulnerable to replay attacks (bsc#962994).
• CVE-2015-8139: Origin Leak: ntpq and ntpdc, disclose origin (bsc#962997).
• CVE-2015-5300: MITM attacker could have forced ntpd to make a step larger than the panic threshold (bsc#951629).
• CVE-2015-7871: NAK to the Future: Symmetric association authentication bypass via crypto-NAK (bsc#951608).
• CVE-2015-7855: decodenetnum() will ASSERT botch instead of returning FAIL on some bogus values (bsc#951608).
• CVE-2015-7854: Password Length Memory Corruption Vulnerability (bsc#951608).
• CVE-2015-7853: Invalid length data provided by a custom refclock driver could cause a buffer overflow (bsc#951608).
• CVE-2015-7852: ntpq atoascii() Memory Corruption Vulnerability (bsc#951608).
• CVE-2015-7851: saveconfig Directory Traversal Vulnerability (bsc#951608).
• CVE-2015-7850: remote config logfile-keyfile (bsc#951608).
• CVE-2015-7849: trusted key use-after-free (bsc#951608).
• CVE-2015-7848: mode 7 loop counter underrun (bsc#951608).
• CVE-2015-7701: Slow memory leak in CRYPTO_ASSOC (bsc#951608).
• CVE-2015-7703: configuration directives 'pidfile' and 'driftfile' should only be allowed locally (bsc#951608).
• CVE-2015-7704, CVE-2015-7705: Clients that receive a KoD should validate the origin timestamp field (bsc#951608).
• CVE-2015-7691, CVE-2015-7692, CVE-2015-7702: Incomplete autokey data packet length checks (bsc#951608).

These non-security issues were fixed:

• fate#320758 bsc#975981: Enable compile-time support for MS-SNTP (--enable-ntp-signd). This replaces the w32 patches in 4.2.4 that added the authreg directive.
• bsc#962318: Call /usr/sbin/sntp with full path to synchronize in start-ntpd. When run as cron job, /usr/sbin/ is not in the path, which caused the synchronization to fail.
• bsc#782060: Speedup ntpq.
• bsc#916617: Add /var/db/ntp-kod.
• bsc#956773: Add ntp-ENOBUFS.patch to limit a warning that might happen quite a lot on loaded systems.
• bsc#951559,bsc#975496: Fix the TZ offset output of sntp during DST.
• Add ntp-fork.patch and build with threads disabled to allow name resolution even when running chrooted.
• Add a controlkey line to /etc/ntp.conf if one does not already exist to allow runtime configuuration via ntpq.
• bsc#946386: Temporarily disable memlock to avoid problems due to high memory usage during name resolution.
• bsc#905885: Use SHA1 instead of MD5 for symmetric keys.
• Improve runtime configuration:
  • Read keytype from ntp.conf
  • Don't write ntp keys to syslog. -…

This update for ntp to 4.2.8p7 fixes the following issues:

• CVE-2016-1547, bsc#977459: Validate crypto-NAKs, AKA: CRYPTO-NAK DoS.
• CVE-2016-1548, bsc#977461: Interleave-pivot
• CVE-2016-1549, bsc#977451: Sybil vulnerability: ephemeral association attack.
• CVE-2016-1550, bsc#977464: Improve NTP security against buffer comparison timing attacks.
• CVE-2016-1551, bsc#977450: Refclock impersonation vulnerability
• CVE-2016-2516, bsc#977452: Duplicate IPs on unconfig directives will cause an assertion botch in ntpd.
• CVE-2016-2517, bsc#977455: remote configuration trustedkey/ requestkey/controlkey values are not properly validated.
• CVE-2016-2518, bsc#977457: Crafted addpeer with hmode > 7 causes array wraparound with MATCH_ASSOC.
• CVE-2016-2519, bsc#977458: ctl_getitem() return value not always checked.
• This update also improves the fixes for: CVE-2015-7704, CVE-2015-7705, CVE-2015-7974

Bugs fixed:

• Restrict the parser in the startup script to the first occurrance of 'keys' and 'controlkey' in ntp.conf (bsc#957226).

This update for ntp to 4.2.8p7 fixes the following issues:

• CVE-2016-1547, bsc#977459: Validate crypto-NAKs, AKA: CRYPTO-NAK DoS.
• CVE-2016-1548, bsc#977461: Interleave-pivot
• CVE-2016-1549, bsc#977451: Sybil vulnerability: ephemeral association attack.
• CVE-2016-1550, bsc#977464: Improve NTP security against buffer comparison timing attacks.
• CVE-2016-1551, bsc#977450: Refclock impersonation vulnerability
• CVE-2016-2516, bsc#977452: Duplicate IPs on unconfig directives will cause an assertion botch in ntpd.
• CVE-2016-2517, bsc#977455: remote configuration trustedkey/ requestkey/controlkey values are not properly validated.
• CVE-2016-2518, bsc#977457: Crafted addpeer with hmode > 7 causes array wraparound with MATCH_ASSOC.
• CVE-2016-2519, bsc#977458: ctl_getitem() return value not always checked.
• This update also improves the fixes for: CVE-2015-7704, CVE-2015-7705, CVE-2015-7974

Bugs fixed:

• Restrict the parser in the startup script to the first occurrance of 'keys' and 'controlkey' in ntp.conf (bsc#957226).

This network time protocol server ntp was updated to 4.2.8p6 to fix the following issues:

Also yast2-ntp-client was updated to match some sntp syntax changes. (bsc#937837)

Major functional changes:

• The 'sntp' commandline tool changed its option handling in a major way.
• 'controlkey 1' is added during update to ntp.conf to allow sntp to work.
• The local clock is being disabled during update.
• ntpd is no longer running chrooted.

Other functional changes:

• ntp-signd is installed.
• 'enable mode7' can be added to the configuration to allow ntdpc to work as compatibility mode option.
• 'kod' was removed from the default restrictions.
• SHA1 keys are used by default instead of MD5 keys.

These security issues were fixed:

• CVE-2015-5219: An endless loop due to incorrect precision to double conversion (bsc#943216).
• CVE-2015-8158: Fixed potential infinite loop in ntpq (bsc#962966).
• CVE-2015-8138: Zero Origin Timestamp Bypass (bsc#963002).
• CVE-2015-7979: Off-path Denial of Service (DoS) attack on authenticated broadcast mode (bsc#962784).
• CVE-2015-7978: Stack exhaustion in recursive traversal of restriction list (bsc#963000).
• CVE-2015-7977: reslist NULL pointer dereference (bsc#962970).
• CVE-2015-7976: ntpq saveconfig command allows dangerous characters in filenames (bsc#962802).
• CVE-2015-7975: nextvar() missing length check (bsc#962988).
• CVE-2015-7974: Skeleton Key: Missing key check allows impersonation between authenticated peers (bsc#962960).
• CVE-2015-7973: Replay attack on authenticated broadcast mode (bsc#962995).
• CVE-2015-8140: ntpq vulnerable to replay attacks (bsc#962994).
• CVE-2015-8139: Origin Leak: ntpq and ntpdc, disclose origin (bsc#962997).
• CVE-2015-5300: MITM attacker could have forced ntpd to make a step larger than the panic threshold (bsc#951629).
• CVE-2015-7871: NAK to the Future: Symmetric association authentication bypass via crypto-NAK (bsc#951608).
• CVE-2015-7855: decodenetnum() will ASSERT botch instead of returning FAIL on some bogus values (bsc#951608).
• CVE-2015-7854: Password Length Memory Corruption Vulnerability (bsc#951608).
• CVE-2015-7853: Invalid length data provided by a custom refclock driver could cause a buffer overflow (bsc#951608).
• CVE-2015-7852: ntpq atoascii() Memory Corruption Vulnerability (bsc#951608).
• CVE-2015-7851: saveconfig Directory Traversal Vulnerability (bsc#951608).
• CVE-2015-7850: remote config logfile-keyfile (bsc#951608).
• CVE-2015-7849: trusted key use-after-free (bsc#951608).
• CVE-2015-7848: mode 7 loop counter underrun (bsc#951608).
• CVE-2015-7701: Slow memory leak in CRYPTO_ASSOC (bsc#951608).
• CVE-2015-7703: configuration directives 'pidfile' and 'driftfile' should only be allowed locally (bsc#951608).
• CVE-2015-7704, CVE-2015-7705: Clients that receive a KoD should validate the origin timestamp field (bsc#951608).
• CVE-2015-7691, CVE-2015-7692, CVE-2015-7702: Incomplete autokey data packet length checks (bsc#951608).

These non-security issues were fixed:

• fate#320758 bsc#975981: Enable compile-time support for MS-SNTP (--enable-ntp-signd). This replaces the w32 patches in 4.2.4 that added the authreg directive.
• bsc#962318: Call /usr/sbin/sntp with full path to synchronize in start-ntpd. When run as cron job, /usr/sbin/ is not in the path, which caused the synchronization to fail.
• bsc#782060: Speedup ntpq.
• bsc#916617: Add /var/db/ntp-kod.
• bsc#956773: Add ntp-ENOBUFS.patch to limit a warning that might happen quite a lot on loaded systems.
• bsc#951559,bsc#975496: Fix the TZ offset output of sntp during DST.
• Add ntp-fork.patch and build with threads disabled to allow name resolution even when running chrooted.
• Add a controlkey line to /etc/ntp.conf if one does not already exist to allow runtime configuuration via ntpq.
• bsc#946386: Temporarily disable memlock to avoid problems due to high memory usage during name resolution.
• bsc#905885: Use SHA1 instead of MD5 for symmetric keys.
• Improve runtime…

This update for ntp fixes the following issues:

• Separate the creation of ntp.keys and key #1 in it to avoid problems when upgrading installations that have the file, but no key #1, which is needed e.g. by 'rcntp addserver'.

• Update to 4.2.8p7 (bsc#977446):

  • CVE-2016-1547, bsc#977459: Validate crypto-NAKs, AKA: CRYPTO-NAK DoS.
  • CVE-2016-1548, bsc#977461: Interleave-pivot
  • CVE-2016-1549, bsc#977451: Sybil vulnerability: ephemeral association attack.
  • CVE-2016-1550, bsc#977464: Improve NTP security against buffer comparison timing attacks.
  • CVE-2016-1551, bsc#977450: Refclock impersonation vulnerability
  • CVE-2016-2516, bsc#977452: Duplicate IPs on unconfig directives will cause an assertion botch in ntpd.
  • CVE-2016-2517, bsc#977455: remote configuration trustedkey/ requestkey/controlkey values are not properly validated.
  • CVE-2016-2518, bsc#977457: Crafted addpeer with hmode > 7 causes array wraparound with MATCH_ASSOC.
  • CVE-2016-2519, bsc#977458: ctl_getitem() return value not always checked.
  • integrate ntp-fork.patch
  • Improve the fixes for: CVE-2015-7704, CVE-2015-7705, CVE-2015-7974

• Restrict the parser in the startup script to the first occurrance of 'keys' and 'controlkey' in ntp.conf (bsc#957226).

ntp was updated to version 4.2.8p8 to fix 17 security issues.

These security issues were fixed:

• CVE-2016-4956: Broadcast interleave (bsc#982068).
• CVE-2016-2518: Crafted addpeer with hmode > 7 causes array wraparound with MATCH_ASSOC (bsc#977457).
• CVE-2016-2519: ctl_getitem() return value not always checked (bsc#977458).
• CVE-2016-4954: Processing spoofed server packets (bsc#982066).
• CVE-2016-4955: Autokey association reset (bsc#982067).
• CVE-2015-7974: NTP did not verify peer associations of symmetric keys when authenticating packets, which might allowed remote attackers to conduct impersonation attacks via an arbitrary trusted key, aka a 'skeleton key (bsc#962960).
• CVE-2016-4957: CRYPTO_NAK crash (bsc#982064).
• CVE-2016-2516: Duplicate IPs on unconfig directives will cause an assertion botch (bsc#977452).
• CVE-2016-2517: Remote configuration trustedkey/requestkey values are not properly validated (bsc#977455).
• CVE-2016-4953: Bad authentication demobilizes ephemeral associations (bsc#982065).
• CVE-2016-1547: CRYPTO-NAK DoS (bsc#977459).
• CVE-2016-1551: Refclock impersonation vulnerability, AKA: refclock-peering (bsc#977450).
• CVE-2016-1550: Improve NTP security against buffer comparison timing attacks, authdecrypt-timing, AKA: authdecrypt-timing (bsc#977464).
• CVE-2016-1548: Interleave-pivot - MITIGATION ONLY (bsc#977461).
• CVE-2016-1549: Sybil vulnerability: ephemeral association attack, AKA: ntp-sybil - MITIGATION ONLY (bsc#977451).

This release also contained improved patches for CVE-2015-7704, CVE-2015-7705, CVE-2015-7974.

These non-security issues were fixed:

• bsc#979302: Change the process name of the forking DNS worker process to avoid the impression that ntpd is started twice.
• bsc#981422: Don't ignore SIGCHILD because it breaks wait().
• bsc#979981: ntp-wait does not accept fractional seconds, so use 1 instead of 0.2 in ntp-wait.service.
• Separate the creation of ntp.keys and key #1 in it to avoid problems when upgrading installations that have the file, but no key #1, which is needed e.g. by 'rcntp addserver'.
• bsc#957226: Restrict the parser in the startup script to the first occurrance of 'keys' and 'controlkey' in ntp.conf.

Aleksis Kauppinen discovered that NTP incorrectly handled certain remote config packets. In a non-default configuration, a remote authenticated attacker could possibly use this issue to cause NTP to crash, resulting in a denial of service. (CVE-2015-5146)

Miroslav Lichvar discovered that NTP incorrectly handled logconfig directives. In a non-default configuration, a remote authenticated attacker could possibly use this issue to cause NTP to crash, resulting in a denial of service. (CVE-2015-5194)

Miroslav Lichvar discovered that NTP incorrectly handled certain statistics types. In a non-default configuration, a remote authenticated attacker could possibly use this issue to cause NTP to crash, resulting in a denial of service. (CVE-2015-5195)

Miroslav Lichvar discovered that NTP incorrectly handled certain file paths. In a non-default configuration, a remote authenticated attacker could possibly use this issue to cause NTP to crash, resulting in a denial of service, or overwrite certain files. (CVE-2015-5196, CVE-2015-7703)

Miroslav Lichvar discovered that NTP incorrectly handled certain packets. A remote attacker could possibly use this issue to cause NTP to hang, resulting in a denial of service. (CVE-2015-5219)

Aanchal Malhotra, Isaac E. Cohen, and Sharon Goldberg discovered that NTP incorrectly handled restarting after hitting a panic threshold. A remote attacker could possibly use this issue to alter the system time on clients. (CVE-2015-5300)

It was discovered that NTP incorrectly handled autokey data packets. A remote attacker could possibly use this issue to cause NTP to crash, resulting in a denial of service, or possibly execute arbitrary code. (CVE-2015-7691, CVE-2015-7692, CVE-2015-7702)

It was discovered that NTP incorrectly handled memory when processing certain autokey messages. A remote attacker could possibly use this issue to cause NTP to consume memory, resulting in a denial of service. (CVE-2015-7701)

Aanchal Malhotra, Isaac E. Cohen, and Sharon Goldberg discovered that NTP incorrectly handled rate limiting. A remote attacker could possibly use this issue to cause clients to stop updating their clock. (CVE-2015-7704, CVE-2015-7705)

Yves Younan discovered that NTP incorrectly handled logfile and keyfile directives. In a non-default configuration, a remote authenticated attacker could possibly use this issue to cause NTP to enter a loop, resulting in a denial of service. (CVE-2015-7850)

Yves Younan and Aleksander Nikolich discovered that NTP incorrectly handled ascii conversion. A remote attacker could possibly use this issue to cause NTP to crash, resulting in a denial of service, or possibly execute arbitrary code. (CVE-2015-7852)

Yves Younan discovered that NTP incorrectly handled reference clock memory. A malicious refclock could possibly use this issue to cause NTP to crash, resulting in a denial of service, or possibly execute arbitrary code. (CVE-2015-7853)

John D "Doug" Birdwell discovered that NTP incorrectly handled decoding certain bogus values. An attacker could possibly use this issue to cause NTP to crash, resulting in a denial of service. (CVE-2015-7855)

Stephen Gray discovered that NTP incorrectly handled symmetric association authentication. A remote attacker could use this issue to possibly bypass authentication and alter the system clock. (CVE-2015-7871)

In the default installation, attackers would be isolated by the NTP AppArmor profile.