{"id":45255,"date":"2026-04-12T04:28:09","date_gmt":"2026-04-12T04:28:09","guid":{"rendered":"http:\/\/localhost\/?p=45255"},"modified":"2026-04-12T04:28:09","modified_gmt":"2026-04-12T04:28:09","slug":"guest-users-can-view-group-member-ids-without-respecting-view-restrictions","status":"publish","type":"post","link":"https:\/\/zero.redgem.net\/?p=45255","title":{"rendered":"Guest users can view group member IDs without respecting view restrictions_CVE-2026-3115"},"content":{"rendered":"<p>{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;Mattermost versions 11.2.x \\u003c= 11.2.2, 10.11.x \\u003c= 10.11.10, 11.4.x \\u003c= 11.4.0, 11.3.x \\u003c= 11.3.1 fail to apply view restrictions when retrieving group member IDs, which allows authenticated guest users to enumerate user IDs outside their allowed visibility scope via the group retrieval endpoint.. 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