CVE-2023-25172: Discourse

Medium severity, CVSS 5.4. EPSS: 0.5% chance of exploitation in the next 30 days.

Discourse is an open-source discussion platform. Prior to version 3.0.1 of the `stable` branch and version 3.1.0.beta2 of the `beta` and `tests-passed` branches, a maliciously crafted URL can be included in a user's full name field to to carry out cross-site scripting attacks on sites with a disabled or overly permissive CSP (Content Security Policy). Discourse's default CSP prevents this vulnerability. The vulnerability is patched in version 3.0.1 of the `stable` branch and version 3.1.0.beta2 of the `beta` and `tests-passed` branches. As a workaround, enable and/or restore your site's CSP to the default one provided with Discourse.

Affected products

• Discourse Discourse: before 3.0.1 (fixed in 3.0.1); before 3.1.0 (fixed in 3.1.0); version 3.1.0 only

Published 2023-03-17. Last modified 2026-06-17.