{"id":62465,"date":"2026-06-12T19:13:26","date_gmt":"2026-06-12T19:13:26","guid":{"rendered":"https:\/\/zero.redgem.net\/?p=62465"},"modified":"2026-06-12T19:13:26","modified_gmt":"2026-06-12T19:13:26","slug":"openclaw-202656-missing-channel-type-validation-in-mattermost-event-handlers","status":"publish","type":"post","link":"https:\/\/zero.redgem.net\/?p=62465","title":{"rendered":"OpenClaw < 2026.5.6 - Missing Channel Type Validation in Mattermost Event Handlers_CVE-2026-53837"},"content":{"rendered":"<p>{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;OpenClaw before 2026.5.6 contains an improper access control vulnerability in Mattermost event handlers that fails to validate channel type metadata. 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