CVE-2021-40516

Publication date 5 September 2021

Last updated 25 August 2025

Ubuntu priority

Cvss 3 Severity Score

Description

WeeChat before 3.2.1 allows remote attackers to cause a denial of service (crash) via a crafted WebSocket frame that trigger an out-of-bounds read in plugins/relay/relay-websocket.c in the Relay plugin.

Status

Show unmaintained releases

Package	Ubuntu Release	Status
weechat	25.04 plucky	Not affected
	24.10 oracular	Not affected
	24.04 LTS noble	Not affected
	23.10 mantic	Not affected
	23.04 lunar	Not affected
	22.10 kinetic	Not affected
	22.04 LTS jammy	Not affected
	21.10 impish	Not affected
	21.04 hirsute	Ignored end of life
	20.04 LTS focal	Fixed 2.8-1ubuntu0.1~esm1
	18.04 LTS bionic	Fixed 1.9.1-1ubuntu1+esm1
	16.04 LTS xenial	Fixed 1.4-2ubuntu0.1+esm1
	14.04 LTS trusty	Not in release

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Severity score breakdown

Parameter	Value
Base score	7.5 · High
Attack vector	Network
Attack complexity	Low
Privileges required	None
User interaction	None
Scope	Unchanged
Confidentiality	None
Integrity impact	None
Availability impact	High
Vector	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References

Related Ubuntu Security Notices (USN)

USN-5258-1
WeeChat vulnerabilities
4 February 2022