CVE-2021-41095

XSS via blocked watched word in error message

Description

Discourse is an open source discussion platform. There is a cross-site scripting (XSS) vulnerability in versions 2.7.7 and earlier of the `stable` branch, versions 2.8.0.beta6 and earlier of the `beta` branch, and versions 2.8.0.beta6 and earlier of the `tests-passed` branch. Rendering of some error messages that contain user input can be susceptible to XSS attacks. This vulnerability only affects sites which have blocked watched words that contain HTML tags, modified or disabled Discourse's default Content Security Policy. This issue is patched in the latest `stable`, `beta` and `tests-passed` versions of Discourse. As a workaround, avoid modifying or disabling Discourse’s default Content Security Policy, and blocking watched words containing HTML tags.

Category

4.2
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.22%
Third-Party Advisory github.com Third-Party Advisory github.com
Affected: discourse discourse
Published at:
Updated at:

References

Link Tags
https://github.com/discourse/discourse/security/advisories/GHSA-qvqx-2h7w-m479 third party advisory
https://github.com/discourse/discourse/pull/14434/commits/40b776b9d39c41d9273d01eecf8fe03aa39fcb59 third party advisory patch

Frequently Asked Questions

What is the severity of CVE-2021-41095?
CVE-2021-41095 has been scored as a medium severity vulnerability.
How to fix CVE-2021-41095?
To fix CVE-2021-41095, 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-2021-41095 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-41095 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-2021-41095?
CVE-2021-41095 affects discourse discourse.
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