Ntp
CVE-2016-1551
LOW
Severity by source
AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
Lifecycle Timeline
1DescriptionCVE.org
ntpd in NTP 4.2.8p3 and NTPsec a5fb34b9cc89b92a8fef2f459004865c93bb7f92 relies on the underlying operating system to protect it from requests that impersonate reference clocks. Because reference clocks are treated like other peers and stored in the same structure, any packet with a source ip address of a reference clock (127.127.1.1 for example) that reaches the receive() function will match that reference clock's peer record and will be treated as a trusted peer. Any system that lacks the typical martian packet filtering which would block these packets is in danger of having its time controlled by an attacker.
AnalysisAI
ntpd in NTP 4.2.8p3 and NTPsec a5fb34b9cc89b92a8fef2f459004865c93bb7f92 relies on the underlying operating system to protect it from requests that impersonate reference clocks. Rated low severity (CVSS 3.7), this vulnerability is remotely exploitable, no authentication required. No vendor patch available.
Technical ContextAI
This vulnerability is classified under CWE-254. ntpd in NTP 4.2.8p3 and NTPsec a5fb34b9cc89b92a8fef2f459004865c93bb7f92 relies on the underlying operating system to protect it from requests that impersonate reference clocks. Because reference clocks are treated like other peers and stored in the same structure, any packet with a source ip address of a reference clock (127.127.1.1 for example) that reaches the receive() function will match that reference clock's peer record and will be treated as a trusted peer. Any system that lacks the typical martian packet filtering which would block these packets is in danger of having its time controlled by an attacker. Affected products include: Ntp, Ntpsec.
RemediationAI
No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.
Crypto-NAK packets in ntpd in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77 allows remote attackers to bypass authen
The monlist feature in ntp_request.c in ntpd in NTP before 4.2.7p26 allows remote attackers to cause a denial of service
The read_mru_list function in NTP before 4.2.8p9 allows remote attackers to cause a denial of service (crash) via a craf
The decodenetnum function in ntpd in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77 allows remote attackers to cause
Multiple stack-based buffer overflows in ntpd in NTP before 4.2.8 allow remote attackers to execute arbitrary code via a
ntpd in NTP before 4.2.8p8 allows remote attackers to cause a denial of service (daemon crash) via a crypto-NAK packet.
util/ntp-keygen.c in ntp-keygen in NTP before 4.2.7p230 uses a weak RNG seed, which makes it easier for remote attackers
The config_auth function in ntpd in NTP before 4.2.7p11, when an auth key is not configured, improperly generates a key,
The datalen parameter in the refclock driver in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77 allows remote attacker
NTP before 4.2.8p6 and 4.3.0 before 4.3.90 allows a remote attackers to cause a denial of service (stack exhaustion) via
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
The panic_gate check in NTP before 4.2.8p5 is only re-enabled after the first change to the system clock that was greate
Same weakness CWE-254 – 7PK - Security Features
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External POC / Exploit Code
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