{"schemaVersion":3,"id":"CVE-2026-3433","aliases":["GHSA-rp4v-qc77-phm4","GO-2026-6286"],"status":"published","duplicateOf":null,"title":null,"description":"Mattermost versions 11.6.x <= 11.6.1, 11.5.x <= 11.5.4, 10.11.x <= 10.11.15, 10.11.x <= 10.11.16 fail to restrict role_updated websocket event broadcasts to members of the affected team or channel which allows an authenticated attacker with guest-level access to observe permission scheme change notifications for private teams they are not a member of via the websocket connection.. 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