CVE-2021-37706

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 STUN message contains an ERROR-CODE attribute, the header length is not checked before performing a subtraction operation, potentially resulting in an integer underflow scenario. This issue affects all users that use STUN. A malicious actor located within the victim’s network may forge and send a specially crafted UDP (STUN) message that could remotely execute arbitrary code on the victim’s machine. Users are advised to upgrade as soon as possible. There are no known workarounds.

• CWE-191
• CWE-191

• http://packetstormsecurity.com/files/166225/Asterisk-Project-Security-Advisory-AST-2022-004.htmlThird Party Advisory, VDB Entry
• http://seclists.org/fulldisclosure/2022/Mar/0Mailing List, Patch, Third Party Advisory
• https://github.com/pjsip/pjproject/commit/15663e3f37091069b8c98a7fce680dc04bc8e865Patch, Third Party Advisory
• https://github.com/pjsip/pjproject/security/advisories/GHSA-2qpg-f6wf-w984Patch, Third Party Advisory
• https://lists.debian.org/debian-lts-announce/2022/03/msg00035.htmlMailing List, Third Party Advisory
• https://lists.debian.org/debian-lts-announce/2022/11/msg00021.htmlMailing List, Third Party Advisory
• https://lists.debian.org/debian-lts-announce/2023/08/msg00038.html
• https://security.gentoo.org/glsa/202210-37Third Party Advisory
• https://www.debian.org/security/2022/dsa-5285Third Party Advisory
• http://packetstormsecurity.com/files/166225/Asterisk-Project-Security-Advisory-AST-2022-004.htmlThird Party Advisory, VDB Entry
• http://seclists.org/fulldisclosure/2022/Mar/0Mailing List, Patch, Third Party Advisory
• https://github.com/pjsip/pjproject/commit/15663e3f37091069b8c98a7fce680dc04bc8e865Patch, Third Party Advisory
• https://github.com/pjsip/pjproject/security/advisories/GHSA-2qpg-f6wf-w984Patch, Third Party Advisory
• https://lists.debian.org/debian-lts-announce/2022/03/msg00035.htmlMailing List, Third Party Advisory
• https://lists.debian.org/debian-lts-announce/2022/11/msg00021.htmlMailing List, Third Party Advisory
• https://lists.debian.org/debian-lts-announce/2023/08/msg00038.html
• https://lists.debian.org/debian-lts-announce/2024/09/msg00030.html
• https://security.gentoo.org/glsa/202210-37Third Party Advisory
• https://www.debian.org/security/2022/dsa-5285Third Party Advisory

Published

Dec 22, 2021

Last Modified

Jun 17, 2026

Status

Modified

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