CVE-2020-11868

Publication date 17 April 2020

Last updated 26 August 2025

Ubuntu priority

Cvss 3 Severity Score

Description

ntpd in ntp before 4.2.8p14 and 4.3.x before 4.3.100 allows an off-path attacker to block unauthenticated synchronization via a server mode packet with a spoofed source IP address, because transmissions are rescheduled even when a packet lacks a valid origin timestamp.

Read the notes from the security team

Status

Show unmaintained releases

Package	Ubuntu Release	Status
ntp	25.10 questing	Not in release
	25.04 plucky	Not in release
	24.10 oracular	Not in release
	24.04 LTS noble	Not in release
	23.10 mantic	Not in release
	23.04 lunar	Not in release
	22.10 kinetic	Not in release
	22.04 LTS jammy	Needs evaluation
	21.10 impish	Ignored end of life
	21.04 hirsute	Ignored end of life
	20.10 groovy	Ignored end of life
	20.04 LTS focal	Needs evaluation
	19.10 eoan	Ignored end of life
	18.04 LTS bionic	Needs evaluation
	16.04 LTS xenial	Needs evaluation
	14.04 LTS trusty	Needs evaluation
ntpsec	25.10 questing	Not affected
	25.04 plucky	Not affected
	24.10 oracular	Not affected
	24.04 LTS noble	Not affected
	23.10 mantic	Ignored end of life, was needs-triage
	23.04 lunar	Ignored end of life, was needs-triage
	22.10 kinetic	Ignored end of life, was needs-triage
	22.04 LTS jammy	Not affected
	21.10 impish	Ignored end of life
	21.04 hirsute	Ignored end of life
	20.10 groovy	Ignored end of life
	20.04 LTS focal	Not affected
	19.10 eoan	Ignored end of life
	18.04 LTS bionic	Not affected
	16.04 LTS xenial	Not in release
	14.04 LTS trusty	Not in release

Notes

bruce

According to upstream NTPsec is not-affected See https://gitlab.com/NTPsec/ntpsec/-/issues/651

Severity score breakdown

Parameter	Value
Base score	5.9 · Medium
Attack vector	Network
Attack complexity	High
Privileges required	None
User interaction	None
Scope	Unchanged
Confidentiality	None
Integrity impact	None
Availability impact	High
Vector	CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H