CVE-2021-43804

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

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.

Category

7.3
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.25%
Vendor Advisory gentoo.org Vendor Advisory debian.org
Affected: pjsip pjproject
Published at:
Updated at:

References

Link Tags
https://github.com/pjsip/pjproject/security/advisories/GHSA-3qx3-cg72-wrh9 third party advisory patch
https://github.com/pjsip/pjproject/commit/8b621f192cae14456ee0b0ade52ce6c6f258af1e third party advisory patch
https://lists.debian.org/debian-lts-announce/2022/03/msg00035.html third party advisory mailing list
https://security.gentoo.org/glsa/202210-37 third party advisory vendor advisory
https://lists.debian.org/debian-lts-announce/2022/11/msg00021.html third party advisory mailing list
https://www.debian.org/security/2022/dsa-5285 third party advisory vendor advisory
https://lists.debian.org/debian-lts-announce/2023/08/msg00038.html mailing list

Frequently Asked Questions

What is the severity of CVE-2021-43804?
CVE-2021-43804 has been scored as a high severity vulnerability.
How to fix CVE-2021-43804?
To fix CVE-2021-43804, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-43804 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-43804 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-43804?
CVE-2021-43804 affects pjsip pjproject.
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