CVE-2023-23621: Discourse vulnerable to ReDoS in user agent parsing

Published Jan 27, 2023
·
Updated

Discourse is an open-source discussion platform. Prior to version 3.0.1 on the stable branch and version 3.1.0.beta2 on the beta and tests-passed branches, a malicious user can cause a regular expression denial of service using a carefully crafted user agent. This issue is patched in version 3.0.1 on the stable branch and version 3.1.0.beta2 on the beta and tests-passed branches. There are no known workarounds.

Affected Software

208 affected components
Discourse Discourse<3.0.1
Discourse Discourse=1.1.0-beta1
Discourse Discourse=1.1.0-beta2
Discourse Discourse=1.1.0-beta3
Discourse Discourse=1.1.0-beta4
Discourse Discourse=1.1.0-beta5
Discourse Discourse=1.1.0-beta6
Discourse Discourse=1.1.0-beta6b
Discourse Discourse=1.1.0-beta7
Discourse Discourse=1.1.0-beta8
Discourse Discourse=1.2.0-beta1
Discourse Discourse=1.2.0-beta2
Discourse Discourse=1.2.0-beta3
Discourse Discourse=1.2.0-beta4
Discourse Discourse=1.2.0-beta5
Discourse Discourse=1.2.0-beta6
Discourse Discourse=1.2.0-beta7
Discourse Discourse=1.2.0-beta8
Discourse Discourse=1.2.0-beta9
Discourse Discourse=1.3.0-beta1
Discourse Discourse=1.3.0-beta10
Discourse Discourse=1.3.0-beta11
Discourse Discourse=1.3.0-beta2
Discourse Discourse=1.3.0-beta3
Discourse Discourse=1.3.0-beta4
Discourse Discourse=1.3.0-beta5
Discourse Discourse=1.3.0-beta6
Discourse Discourse=1.3.0-beta7
Discourse Discourse=1.3.0-beta8
Discourse Discourse=1.3.0-beta9
Discourse Discourse=1.4.0-beta1
Discourse Discourse=1.4.0-beta10
Discourse Discourse=1.4.0-beta11
Discourse Discourse=1.4.0-beta12
Discourse Discourse=1.4.0-beta2
Discourse Discourse=1.4.0-beta3
Discourse Discourse=1.4.0-beta4
Discourse Discourse=1.4.0-beta5
Discourse Discourse=1.4.0-beta6
Discourse Discourse=1.4.0-beta7
Discourse Discourse=1.4.0-beta8
Discourse Discourse=1.4.0-beta9
Discourse Discourse=1.5.0-beta1
Discourse Discourse=1.5.0-beta10
Discourse Discourse=1.5.0-beta11
Discourse Discourse=1.5.0-beta12
Discourse Discourse=1.5.0-beta13
Discourse Discourse=1.5.0-beta13b
Discourse Discourse=1.5.0-beta14
Discourse Discourse=1.5.0-beta2
Discourse Discourse=1.5.0-beta3
Discourse Discourse=1.5.0-beta4
Discourse Discourse=1.5.0-beta5
Discourse Discourse=1.5.0-beta6
Discourse Discourse=1.5.0-beta7
Discourse Discourse=1.5.0-beta8
Discourse Discourse=1.5.0-beta9
Discourse Discourse=1.6.0-beta1
Discourse Discourse=1.6.0-beta10
Discourse Discourse=1.6.0-beta11
Discourse Discourse=1.6.0-beta12
Discourse Discourse=1.6.0-beta2
Discourse Discourse=1.6.0-beta3
Discourse Discourse=1.6.0-beta4
Discourse Discourse=1.6.0-beta5
Discourse Discourse=1.6.0-beta6
Discourse Discourse=1.6.0-beta7
Discourse Discourse=1.6.0-beta8
Discourse Discourse=1.6.0-beta9
Discourse Discourse=1.7.0-beta1
Discourse Discourse=1.7.0-beta10
Discourse Discourse=1.7.0-beta11
Discourse Discourse=1.7.0-beta2
Discourse Discourse=1.7.0-beta3
Discourse Discourse=1.7.0-beta4
Discourse Discourse=1.7.0-beta5
Discourse Discourse=1.7.0-beta6
Discourse Discourse=1.7.0-beta7
Discourse Discourse=1.7.0-beta8
Discourse Discourse=1.7.0-beta9
Discourse Discourse=1.8.0-beta1
Discourse Discourse=1.8.0-beta10
Discourse Discourse=1.8.0-beta11
Discourse Discourse=1.8.0-beta12
Discourse Discourse=1.8.0-beta13
Discourse Discourse=1.8.0-beta2
Discourse Discourse=1.8.0-beta3
Discourse Discourse=1.8.0-beta4
Discourse Discourse=1.8.0-beta5
Discourse Discourse=1.8.0-beta6
Discourse Discourse=1.8.0-beta7
Discourse Discourse=1.8.0-beta8
Discourse Discourse=1.8.0-beta9
Discourse Discourse=1.9.0-beta1
Discourse Discourse=1.9.0-beta10
Discourse Discourse=1.9.0-beta11
Discourse Discourse=1.9.0-beta12
Discourse Discourse=1.9.0-beta13
Discourse Discourse=1.9.0-beta14
Discourse Discourse=1.9.0-beta15
Discourse Discourse=1.9.0-beta16
Discourse Discourse=1.9.0-beta17
Discourse Discourse=1.9.0-beta2
Discourse Discourse=1.9.0-beta3
Discourse Discourse=1.9.0-beta4
Discourse Discourse=1.9.0-beta5
Discourse Discourse=1.9.0-beta6
Discourse Discourse=1.9.0-beta7
Discourse Discourse=1.9.0-beta8
Discourse Discourse=1.9.0-beta9
Discourse Discourse=2.0.0-beta1
Discourse Discourse=2.0.0-beta10
Discourse Discourse=2.0.0-beta2
Discourse Discourse=2.0.0-beta3
Discourse Discourse=2.0.0-beta4
Discourse Discourse=2.0.0-beta5
Discourse Discourse=2.0.0-beta6
Discourse Discourse=2.0.0-beta7
Discourse Discourse=2.0.0-beta8
Discourse Discourse=2.0.0-beta9
Discourse Discourse=2.1.0-beta1
Discourse Discourse=2.1.0-beta2
Discourse Discourse=2.1.0-beta3
Discourse Discourse=2.1.0-beta4
Discourse Discourse=2.1.0-beta5
Discourse Discourse=2.1.0-beta6
Discourse Discourse=2.2.0-beta1
Discourse Discourse=2.2.0-beta10
Discourse Discourse=2.2.0-beta2
Discourse Discourse=2.2.0-beta3
Discourse Discourse=2.2.0-beta4
Discourse Discourse=2.2.0-beta5
Discourse Discourse=2.2.0-beta6
Discourse Discourse=2.2.0-beta7
Discourse Discourse=2.2.0-beta8
Discourse Discourse=2.2.0-beta9
Discourse Discourse=2.3.0-beta1
Discourse Discourse=2.3.0-beta10
Discourse Discourse=2.3.0-beta11
Discourse Discourse=2.3.0-beta2
Discourse Discourse=2.3.0-beta3
Discourse Discourse=2.3.0-beta4
Discourse Discourse=2.3.0-beta5
Discourse Discourse=2.3.0-beta6
Discourse Discourse=2.3.0-beta7
Discourse Discourse=2.3.0-beta8
Discourse Discourse=2.3.0-beta9
Discourse Discourse=2.4.0-beta1
Discourse Discourse=2.4.0-beta10
Discourse Discourse=2.4.0-beta11
Discourse Discourse=2.4.0-beta2
Discourse Discourse=2.4.0-beta3
Discourse Discourse=2.4.0-beta4
Discourse Discourse=2.4.0-beta5
Discourse Discourse=2.4.0-beta6
Discourse Discourse=2.4.0-beta7
Discourse Discourse=2.4.0-beta8
Discourse Discourse=2.4.0-beta9
Discourse Discourse=2.5.0-beta1
Discourse Discourse=2.5.0-beta2
Discourse Discourse=2.5.0-beta3
Discourse Discourse=2.5.0-beta4
Discourse Discourse=2.5.0-beta5
Discourse Discourse=2.5.0-beta6
Discourse Discourse=2.5.0-beta7
Discourse Discourse=2.6.0-beta1
Discourse Discourse=2.6.0-beta2
Discourse Discourse=2.6.0-beta3
Discourse Discourse=2.6.0-beta4
Discourse Discourse=2.6.0-beta5
Discourse Discourse=2.6.0-beta6
Discourse Discourse=2.7.0-beta1
Discourse Discourse=2.7.0-beta2
Discourse Discourse=2.7.0-beta3
Discourse Discourse=2.7.0-beta4
Discourse Discourse=2.7.0-beta5
Discourse Discourse=2.7.0-beta6
Discourse Discourse=2.7.0-beta7
Discourse Discourse=2.7.0-beta8
Discourse Discourse=2.7.0-beta9
Discourse Discourse=2.8.0-beta1
Discourse Discourse=2.8.0-beta10
Discourse Discourse=2.8.0-beta11
Discourse Discourse=2.8.0-beta2
Discourse Discourse=2.8.0-beta3
Discourse Discourse=2.8.0-beta4
Discourse Discourse=2.8.0-beta5
Discourse Discourse=2.8.0-beta6
Discourse Discourse=2.8.0-beta7
Discourse Discourse=2.8.0-beta8
Discourse Discourse=2.8.0-beta9
Discourse Discourse=2.9.0-beta1
Discourse Discourse=2.9.0-beta10
Discourse Discourse=2.9.0-beta11
Discourse Discourse=2.9.0-beta12
Discourse Discourse=2.9.0-beta13
Discourse Discourse=2.9.0-beta14
Discourse Discourse=2.9.0-beta2
Discourse Discourse=2.9.0-beta3
Discourse Discourse=2.9.0-beta4
Discourse Discourse=2.9.0-beta5
Discourse Discourse=2.9.0-beta6
Discourse Discourse=2.9.0-beta7
Discourse Discourse=2.9.0-beta8
Discourse Discourse=2.9.0-beta9
Discourse Discourse=3.0.0-beta15
Discourse Discourse=3.0.0-beta16
Discourse Discourse=3.1.0-beta1

Event History

Jan 27, 2023
CVE Published
via MITRE·11:31 PM
Data Sourced
via MITRE·11:31 PM
DescriptionSeverityWeakness

Frequently Asked Questions

1

What is the severity of CVE-2023-23621?

CVE-2023-23621 has a critical severity rating due to its potential for regular expression denial of service attacks.

2

How do I fix CVE-2023-23621?

To mitigate CVE-2023-23621, upgrade to Discourse version 3.0.1 or later on the stable branch, or version 3.1.0.beta2 or later on the beta and tests-passed branches.

3

Who is affected by CVE-2023-23621?

Discourse users running versions prior to 3.0.1 on the stable branch and 3.1.0.beta2 on beta or tests-passed branches are affected by CVE-2023-23621.

4

What can attackers do with CVE-2023-23621?

Attackers can exploit CVE-2023-23621 to launch denial of service attacks by sending specially crafted user agents that trigger excessive regex processing.

5

Is there a patch available for CVE-2023-23621?

Yes, CVE-2023-23621 is patched in Discourse version 3.0.1 and later.

Contact

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