CVE-2023-23621

Discourse vulnerable to ReDoS in user agent parsing

Description

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.

Category

8.6
CVSS
Severity: High
CVSS 3.1 •
EPSS 0.07%
Third-Party Advisory github.com
Affected: discourse discourse
Published at:
Updated at:

References

Link Tags
https://github.com/discourse/discourse/security/advisories/GHSA-mrfp-54hf-jrcv third party advisory
https://github.com/discourse/discourse/pull/20002 issue tracking patch
https://github.com/discourse/discourse/commit/6d92c3cbdac431db99a450f360a3048bb3aaf458 patch

Frequently Asked Questions

What is the severity of CVE-2023-23621?
CVE-2023-23621 has been scored as a high severity vulnerability.
How to fix CVE-2023-23621?
To fix CVE-2023-23621, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2023-23621 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2023-23621 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2023-23621?
CVE-2023-23621 affects discourse discourse.
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