Vulnerability · Published Mar 31, 2026 · Assigned by GitHub_M

CVE-2026-33300Discourse: Hidden group names and access metadata are exposed to moderators through the `category-chatables` endpoint

Medium 5.3

In plain English

A medium-severity information exposure 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 0.2% (higher than 16% of all known vulnerabilities).

Severity (CVSS 4.0)5.3Medium

Exploit odds (30 days)0.2%top 84.4% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

Discourse is an open-source discussion platform. From versions 2026.1.0-latest to before 2026.1.3, 2026.2.0-latest to before 2026.2.2, and 2026.3.0-latest to before 2026.3.0, an authorization bypass in the Category Chatables Controller show action allowed moderators to get information on hidden groups names and user count. This issue has been patched in versions 2026.1.3, 2026.2.2, and 2026.3.0.

Affected products (as reported)

Vendor	Product	Versions
discourse	discourse	>= 2026.1.0-latest, < 2026.1.3>= 2026.2.0-latest, < 2026.2.2>= 2026.3.0-latest, < 2026.3.0

Weakness: CWE-200 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N

References

https://github.com/discourse/discourse/security/advisories/GHSA-wrwm-vqx2-6x4v x_refsource_CONFIRM
https://github.com/discourse/discourse/commit/07f66658cce81a099a0d7115db5f3c69f5d3cca2 x_refsource_MISC