CVE-2016-1549

Publication date 6 January 2017

Last updated 25 August 2025

Ubuntu priority

Cvss 3 Severity Score

Description

A malicious authenticated peer can create arbitrarily-many ephemeral associations in order to win the clock selection algorithm in ntpd in NTP 4.2.8p4 and earlier and NTPsec 3e160db8dc248a0bcb053b56a80167dc742d2b74 and a5fb34b9cc89b92a8fef2f459004865c93bb7f92 and modify a victim's clock.

Read the notes from the security team

Status

Show unmaintained releases

Package	Ubuntu Release	Status
ntp	16.04 LTS xenial	Ignored
	15.10 wily	Ignored
	14.04 LTS trusty	Ignored
	12.04 LTS precise	Ignored

Notes

mdeslaur

upstream proposes mitigation only

Severity score breakdown

CVSS version: CVSS v3.0

Base score 6.5 · Medium

Base metrics

Parameter	Value
Attack vector	Network
Attack complexity	Low
Privileges required	Low
User interaction	None
Scope	Unchanged
Confidentiality impact	None
Integrity impact	High
Availability impact	None

Scores

Parameter	Value
Base score	6.5 · Medium
Exploitability score	-
Impact score	-

Vector: CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N