SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2016-1551

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.

LOW 3.7EPSS 2.23%

Does this matter?

Lower severity and a low EPSS score (2.23%). Track it; it rarely justifies an emergency change on its own.

Description

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.

CVSS 3.0
3.7 LOWCVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
EPSS
2.23% probability · 82th percentile
CISA KEV
Not listed
Weakness
CWE-254
Affected
ntp/ntp · ntpsec/ntpsec
Source
cret@cert.org

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.