CVE-2021-39161

Cross-site scripting via category name in Discourse

Description

Discourse is an open source platform for community discussion. In affected versions category names can be used for Cross-site scripting(XSS) attacks. This is mitigated by Discourse's default Content Security Policy and this vulnerability only affects sites which have modified or disabled or changed Discourse's default Content Security Policy have allowed for moderators to modify categories. This issue is patched in the latest stable, beta and tests-passed versions of Discourse. Users are advised to ensure that the Content Security Policy is enabled, and has not been modified in a way which would make it more vulnerable to XSS attacks.

Category

4.4
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.21%
Third-Party Advisory github.com
Affected: discourse discourse
Published at:
Updated at:

References

Link Tags
https://github.com/discourse/discourse/security/advisories/GHSA-xhmc-9jwm-wqph third party advisory

Frequently Asked Questions

What is the severity of CVE-2021-39161?
CVE-2021-39161 has been scored as a medium severity vulnerability.
How to fix CVE-2021-39161?
To fix CVE-2021-39161, 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-2021-39161 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-39161 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-2021-39161?
CVE-2021-39161 affects discourse discourse.
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