CVE-2021-21375

Publication date 10 March 2021

Last updated 24 March 2026

Ubuntu priority

Cvss 3 Severity Score

Description

PJSIP is a free and open source multimedia communication library written in C language implementing standard based protocols such as SIP, SDP, RTP, STUN, TURN, and ICE. In PJSIP version 2.10 and earlier, after an initial INVITE has been sent, when two 183 responses are received, with the first one causing negotiation failure, a crash will occur. This results in a denial of service.

Status

Show unmaintained releases

Package	Ubuntu Release	Status
pjproject	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	Not in release
	21.10 impish	Not in release
	21.04 hirsute	Not in release
	20.10 groovy	Not in release
	20.04 LTS focal	Not in release
	18.04 LTS bionic	Fixed 2.7.2~dfsg-1ubuntu0.1~esm1
	16.04 LTS xenial	Fixed 2.1.0.0.ast20130823-1+deb8u1ubuntu0.1~esm1
	14.04 LTS trusty	Not in release

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Patch details

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

Package	Patch details
pjproject	Upstream: 97b3d7a

Severity score breakdown

Parameter	Value
Base score	6.5 · Medium
Attack vector	Network
Attack complexity	Low
Privileges required	None
User interaction	Required
Scope	Unchanged
Confidentiality	None
Integrity impact	None
Availability impact	High
Vector	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

References

Related Ubuntu Security Notices (USN)

USN-8122-1
PJSIP vulnerabilities
24 March 2026