Out-of-bounds Read in Pjsip Pjproject

CVE-2021-43804

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.

Vulnerability class: Buffer Overflow

EPSS: 0.022 (80.6th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.3 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2021-43804?
CVE-2021-43804 is a high-severity vulnerability in Pjsip Pjproject, classified under Out-of-bounds Read. CVSS score: 7.3/10. Published 2021-12-22.
How severe is CVE-2021-43804?
High severity. CVSS v3 base score is 7.3 out of 10.
Is CVE-2021-43804 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.