CVE-2016-1551

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.

Category

3.7
CVSS
Severity: Low
CVSS 3.0 •
CVSS 2.0 •
EPSS 0.64%
Vendor Advisory FreeBSD.org Vendor Advisory gentoo.org
Affected: NTP Project NTP
Affected: NTPsec Project NTPSec
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2016-1551?
CVE-2016-1551 has been scored as a low severity vulnerability.
How to fix CVE-2016-1551?
To fix CVE-2016-1551, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2016-1551 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2016-1551 is being actively exploited. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2016-1551?
CVE-2016-1551 affects NTP Project NTP, NTPsec Project NTPSec.
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