CVE-2021-43804: Out-of-bounds read when parsing RTCP BYE message in PJSIP

Published Dec 22, 2021
·
Updated

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.

Affected Software

7 affected componentsFixes available
debian/asterisk
1:16.28.0~dfsg-0+deb10u41:16.28.0~dfsg-0+deb11u31:16.28.0~dfsg-0+deb11u41:20.6.0~dfsg+~cs6.13.40431414-2
debian/ring<=20190215.1.f152c98~ds1-1+deb10u1, <=20210112.2.b757bac~ds1-1
20190215.1.f152c98~ds1-1+deb10u220230206.0~ds2-1.120231201.0~ds1-1
ubuntu/ring<20180228.1.503
20180228.1.503
ubuntu/ring<20190215.1.
20190215.1.
Teluu PJSIP<=2.11.1
Debian Debian Linux=9.0
Debian Debian Linux=10.0

Event History

Dec 22, 2021
CVE Published
via MITRE·12:00 AM
Data Sourced
via MITRE·12:00 AM
DescriptionSeverityWeakness
Data Sourced
via NVD·06:15 PM
RemedyDescriptionSeverityWeaknessAffected Software
Jan 12, 2024
Data Sourced
via Launchpad·12:01 AM
Description

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is CVE-2021-43804?

CVE-2021-43804 is a vulnerability in the PJSIP multimedia communication library that allows remote attackers to cause a denial of service (DoS) by sending a specially crafted RTCP BYE message.

2

How severe is CVE-2021-43804?

CVE-2021-43804 has a severity rating of 7.3, which is considered high.

3

Which software versions are affected by CVE-2021-43804?

The affected software versions include Teluu Pjsip up to version 2.11.1, Debian Debian Linux version 9.0 and 10.0, and Asterisk version up to 1:16.2.1~dfsg-1+deb10u2.

4

How can I fix CVE-2021-43804?

To fix CVE-2021-43804, update to the latest version of PJSIP, Debian Linux, or Asterisk, depending on your affected software.

5

Is there any additional information about CVE-2021-43804?

Yes, you can find additional information about CVE-2021-43804 in the provided references.

Contact

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