CVE-2021-20234: Medium severity libzmq5 vulnerability

Published Jan 29, 2021
·
Updated

A flaw was found in zeromq before 4.3.3. When a pipe processes a delimiter and is already not in active state but still has an unfinished message, the message is leaked causing a crash.

References:

https://github.com/zeromq/libzmq/pull/3918 https://github.com/zeromq/libzmq/security/advisories/GHSA-wfr2-29gj-5w87 https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=22037 https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=22123

Other sources

An uncontrolled resource consumption (memory leak) flaw was found in the ZeroMQ client in versions before 4.3.3 in src/pipe.cpp. This issue causes a client that connects to multiple malicious or compromised servers to crash. The highest threat from this vulnerability is to system availability.

Launchpad

Affected Software

3 affected componentsFixes available
redhat/zeromq<4.3.3
4.3.3
debian/zeromq3
4.3.4-1+deb11u14.3.4-64.3.5-1
ZeroMQ libzmq<4.3.3

Event History

Apr 1, 2021
CVE Published
via MITRE·01:46 PM
Data Sourced
via MITRE·01:46 PM
DescriptionWeakness
Jan 11, 2024
Data Sourced
via Launchpad·11:53 PM
Description
Sep 14, 2024
Data Sourced
via Ubuntu·10:12 PM
RemedyDescriptionSeverityAffected Software
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Frequently Asked Questions

1

What is CVE-2021-20234?

CVE-2021-20234 is an uncontrolled resource consumption (memory leak) vulnerability in the ZeroMQ client.

2

What is the severity of CVE-2021-20234?

The severity of CVE-2021-20234 is medium with a CVSS score of 6.5.

3

Which software versions are affected by CVE-2021-20234?

Versions before 4.3.3 of the ZeroMQ client are affected.

4

How does CVE-2021-20234 impact system availability?

CVE-2021-20234 can cause a system to crash if a client connects to multiple malicious or compromised servers.

5

How can I fix CVE-2021-20234?

To fix CVE-2021-20234, upgrade to version 4.3.3-1 of the ZeroMQ client.

Contact

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