CVE-2021-43804

Out-of-bounds read when parsing RTCP BYE message in PJSIP

HIGH
7.3
CVSS Score
Published: December 22, 2021 at 12:00 AM UTC
Updated: June 17, 2026 at 04:11 AM UTC
3 products affected across 3 vendorsDebian LinuxPjsipPjsip

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Severity
HIGH7.3
Exploit prediction
EPSS 2%

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 affected versions if the incoming RTCP BYE message contains a reason's length, this declared length is not checked against the actual received packet size, potentially resulting in an out-of-bound read access. This issue affects all users that use PJMEDIA and RTCP. A malicious actor can send a RTCP BYE message with an invalid reason length. Users are advised to upgrade as soon as possible. There are no known workarounds.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

CVSS

7.3HIGHGitHub_M
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
LOW
Integrity
LOW
Availability
LOW
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-125

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