Details for this vulnerability have not been published by NIST at this point. Descriptions from software vendor advisories for this issue are provided below.
From USN-2783-1:
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.
From DSA-3388:
Several vulnerabilities were discovered in the Network Time Protocol
daemon and utility programs:
From ALAS-2015-593:
Asdiscussed upstream, a flaw was found in the way ntpd processed certain remote configuration packets. Note that remote configuration is disabled by default in NTP. (CVE-2015-5146)
It was found that the :config command can be used to set the pidfile and driftfile paths without any restrictions. A remote attacker could use this flaw to overwrite a file on the file system with a file containing the pid of the ntpd process (immediately) or the current estimated drift of the system clock (in hourly intervals). (CVE-2015-7703)
It was found that ntpd could crash due to an uninitialized variable when processing malformed logconfig configuration commands. (CVE-2015-5194)
It was found that ntpd exits with a segmentation fault when a statistics type that was not enabled during compilation (e.g. timingstats) is referenced by the statistics or filegen configuration command. (CVE-2015-5195)
It was discovered that sntp would hang in an infinite loop when a crafted NTP packet was received, related to the conversion of the precision value in the packet to double. (CVE-2015-5219)
A flaw was found in the way the ntp-keygen utility generated MD5 symmetric keys on big-endian systems. An attacker could possibly use this flaw to guess generated MD5 keys, which could then be used to spoof an NTP client or server. (CVE-2015-3405)
From K17114:
For BIG-IP systems using a default network time protocol (NTP) configuration, there is no impact. However, BIG-IP systems with an NTP configuration that is customized in line with the requirements of the advisory may be vulnerable.
From DLA-335-1:
ntp - security update
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