SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2021-43804

A malicious actor can send a RTCP BYE message with an invalid reason length.

HIGH 7.3EPSS 2.19%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (2.19%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

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 3.1
7.3 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
EPSS
2.19% probability · 81th percentile
CISA KEV
Not listed
Weakness
CWE-125
Affected
teluu/pjsip · debian/debian linux
Source
security-advisories@github.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.