CVE-2021-37706

HIGHScheduled

Published:Dec 22, 2021(4 years ago)

Modified:Nov 4, 2025

Remote ExploitNo Auth RequiredNo InteractionLow Complexity

Vulnerability 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 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.

Attack Characteristics

Network AccessLow ComplexityNo Auth NeededNo User Interaction

🤖

AI analysis not yet available

Plain-English explanation, risk summary, and remediation steps will appear here once AI analysis is complete.

No Fix Known

No patch has been released yet. Apply workarounds or mitigations where available.

Affected Software

Vendor	Product	Versions	Fixed In
teluu	pjsip	2.11.1	-
asterisk	certified_asterisk	16.8.0

Timeline

Published
CVE disclosed publicly
Dec 22, 20214 years ago
Last Modified
Most recent update
Nov 4, 20257 months ago
Indexed to CVEInsight
Added to this platform
Mar 29, 20262 months ago

References

http://packetstormsecurity.com/files/166225/Asterisk-Project-Security-...Third Party Advisory
http://seclists.org/fulldisclosure/2022/Mar/0Mailing List
https://github.com/pjsip/pjproject/commit/15663e3f37091069b8c98a7fce68...Patch

CVSS Score

v3.1

7.3/ 10.0

HIGH

AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L

At a Glance

Affected Products

References

teluu / pjsip

https://github.com/pjsip/pjproject/security/advisories/GHSA-2qpg-f6wf-...Patch

https://lists.debian.org/debian-lts-announce/2022/03/msg00035.htmlMailing List

https://lists.debian.org/debian-lts-announce/2022/11/msg00021.htmlMailing List

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-...Third Party Advisory

http://seclists.org/fulldisclosure/2022/Mar/0Mailing List

https://github.com/pjsip/pjproject/commit/15663e3f37091069b8c98a7fce68...Patch

https://github.com/pjsip/pjproject/security/advisories/GHSA-2qpg-f6wf-...Patch

https://lists.debian.org/debian-lts-announce/2022/03/msg00035.htmlMailing List

https://lists.debian.org/debian-lts-announce/2022/11/msg00021.htmlMailing List

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

CVSS v3 Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L

Exploitability

Attack VectorNetwork

Attack ComplexityLow

Privileges RequiredNone

User InteractionNone

Impact

ScopeUnchanged

ConfidentialityLow

IntegrityLow

AvailabilityLow

Impact Analysis

ConfidentialityLow

NoneLowHigh

IntegrityLow

NoneLowHigh

AvailabilityLow

NoneLowHigh

CVE-2021-37706

✦ Vulnerability Description

Attack Characteristics

Affected Software

Timeline

References

CVSS Score

At a Glance

Official Sources

CVSS v3 Vector

Impact Analysis

Vulnerability Description