{"id":55232,"date":"2026-05-18T03:45:40","date_gmt":"2026-05-18T03:45:40","guid":{"rendered":"https:\/\/zero.redgem.net\/?p=55232"},"modified":"2026-05-18T03:45:40","modified_gmt":"2026-05-18T03:45:40","slug":"mattermost-fails-to-enforce-createpost-permission-when-editing-posts","status":"publish","type":"post","link":"https:\/\/zero.redgem.net\/?p=55232","title":{"rendered":"Mattermost fails to enforce create_post permission when editing posts_CVE-2026-3637"},"content":{"rendered":"<p>{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;Mattermost versions 11.5.x \\u003c= 11.5.1, 10.11.x \\u003c= 10.11.13, 11.4.x \\u003c= 11.4.3 fail to check the create_post channel permission during post edit operations which allows an authenticated attacker with revoked posting privileges to modify their existing posts via direct API requests to the post update and patch endpoints.. 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