Vulnerability · Published Mar 20, 2026 · Assigned by GitHub_M
CVE-2026-33425Discourse has inferable private group membership or existence via exclude_groups parameter
Medium 6.9
In plain English
A medium-severity authorization bypass via user-controlled key in discourse from discourse. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.7% (higher than 53% of all known vulnerabilities). Ready-made attack tooling exists: Nuclei.
Official description
Discourse is an open-source discussion platform. Prior to versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2, unauthenticated users can determine whether a specific user is a member of a private group by observing changes in directory results when using the `exclude_groups` parameter. Versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2 contain a patch. As a workaround, disable public access to the user directory via Admin → Settings → hide user profiles from public.
Affected products (as reported)
Weakness: CWE-203, CWE-639, CWE-862 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N
References
- https://github.com/discourse/discourse/security/advisories/GHSA-r6rh-xvf5-r5f2 x_refsource_CONFIRM