High severity · published Dec 22, 2021
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
7.3
CVSS
2.3%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
Low
Integrity
Low
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)2.3% · higher than 83% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DL
Debian Linux · Debian
9.0; 10.0 · source: NVD
PJ
Pjsip · Teluu
through 2.11.1 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-43804
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-43804
Patch
https://github.com/pjsip/pjproject/commit/8b621f192cae14456ee0b0ade52ce6c6f258af1e
Patch
https://github.com/pjsip/pjproject/security/advisories/GHSA-3qx3-cg72-wrh9
Mailing List
https://lists.debian.org/debian-lts-announce/2022/03/msg00035.html
Mailing List
https://lists.debian.org/debian-lts-announce/2022/11/msg00021.html
lists.debian.org
https://lists.debian.org/debian-lts-announce/2023/08/msg00038.html
Third Party Advisory
https://security.gentoo.org/glsa/202210-37
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