CVE-2026-33300mediumCWE-200

CVE-2026-33300: medium-severity vulnerability in discourse

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

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13Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 5.3epss 0.2%
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.
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
Affected products
discourse · discourse
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