CVE-2021-32686 Denial of Service in PJSIP

What is CVE-2021-32686?

CVE-2021-32686 is a medium-severity vulnerability in Debian Debian Linux, published on 23 Jul 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official 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 before version 2.11.1, there are a couple of issues found in the SSL socket. First, a race condition between callback and destroy, due to the accepted socket having no group lock. Second, the SSL socket parent/listener may get destroyed during handshake. Both issues were reported to happen intermittently in heavy load TLS connections. They cause a crash, resulting in a denial of service. These are fixed in version 2.11.1.

Weakness: CWE-362

Which versions are affected by CVE-2021-32686?

It affects 2 products.

Products include Debian Debian Linux, Teluu Pjsip.

How do I fix CVE-2021-32686?

Upgrade to a fixed version.

Is CVE-2021-32686 being exploited?

There is no known exploitation of CVE-2021-32686 in the wild and no public exploit code.

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All Debian Debian Linux vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as ALPINE-CVE-2021-32686, DEBIAN-CVE-2021-32686, GHSA-cv8x-p47p-99wr, MGASA-2021-0559, UBUNTU-CVE-2021-32686.