{"id":"CVE-2026-2578","details":"Mattermost versions 11.3.x \u003c= 11.3.0 fail to preserve the redacted state of burn-on-read posts during deletion which allows channel members to access unrevealed burn-on-read message contents via the WebSocket post deletion event.. Mattermost Advisory ID: MMSA-2026-00579","aliases":["GHSA-3rhr-jr63-hwq5","GO-2026-4734"],"modified":"2026-04-02T13:18:10.746425Z","published":"2026-03-16T14:19:30.840Z","related":["SUSE-SU-2026:1135-1"],"references":[{"type":"ADVISORY","url":"https://mattermost.com/security-updates"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/mattermost/mattermost-server","events":[{"introduced":"d27a2195068ddfa3ce17cf470f9739e4edb94b83"},{"fixed":"4082c3dcf285e4d1a386d2ef37f14f39dc5a0094"}],"database_specific":{"versions":[{"introduced":"11.3.0"},{"fixed":"11.3.1"}]}}],"versions":["@mattermost/client@11.3.0","@mattermost/types@11.3.0","mattermost-redux@11.3.0","v11.3.0","v11.3.0-rc3","v11.3.0-rc4","v11.3.1-rc1"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-2578.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N"}]}