CVE-2016-1551

Publication date 27 January 2017

Last updated 24 July 2024

Ubuntu priority

Cvss 3 Severity Score

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.

Read the notes from the security team

Status

Show unmaintained releases

Package	Ubuntu Release	Status
ntp	16.04 LTS xenial	Not affected
	15.10 wily	Not affected
	14.04 LTS trusty	Not affected
	12.04 LTS precise	Not affected

Notes

mdeslaur

Linux drops 127.0.0.0/8, Ubuntu not affected

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package	Patch details
ntp	Upstream: http://bk1.ntp.org/ntp-stable/?PAGE=patch&REV=56d4cdadyjbEtsWIuGaFIpsC0XrP2A

Severity score breakdown

Parameter	Value
Base score	3.7 · Low
Attack vector	Network
Attack complexity	High
Privileges required	None
User interaction	None
Scope	Unchanged
Confidentiality	None
Integrity impact	Low
Availability impact	None
Vector	CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N