CVE-2021-21375

Public Exploit
Crash in receiving updated SDP answer after initial SDP negotiation failed

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 PJSIP version 2.10 and earlier, after an initial INVITE has been sent, when two 183 responses are received, with the first one causing negotiation failure, a crash will occur. This results in a denial of service.

Categories

6.5
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 2.31% Top 20%
Vendor Advisory gentoo.org
Affected: pjsip pjproject
Published at:
Updated at:

References

Link Tags
https://github.com/pjsip/pjproject/security/advisories/GHSA-hvq6-f89p-frvp patch third party advisory exploit
https://github.com/pjsip/pjproject/commit/97b3d7addbaa720b7ddb0af9bf6f3e443e664365 third party advisory patch
https://lists.debian.org/debian-lts-announce/2021/04/msg00023.html third party advisory mailing list
https://lists.debian.org/debian-lts-announce/2021/05/msg00020.html third party advisory mailing list
https://security.gentoo.org/glsa/202107-42 third party advisory vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-21375?
CVE-2021-21375 has been scored as a medium severity vulnerability.
How to fix CVE-2021-21375?
To fix CVE-2021-21375, 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-2021-21375 being actively exploited in the wild?
It is possible that CVE-2021-21375 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~2% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-21375?
CVE-2021-21375 affects pjsip pjproject.
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