{"id":"CVE-2026-10542","title":"Mattermost versions 11.9.x <= 11.9.0, 11.8.x <= 11.8.4, 11.7.x <= 11.7.7, 10.11.x <= 10.11.22 fail to validate channel action ownership which allows channel managers to update actions in other channels via the channel action update endpo…","summary":"Mattermost versions 11.9.x <= 11.9.0, 11.8.x <= 11.8.4, 11.7.x <= 11.7.7, 10.11.x <= 10.11.22 fail to validate channel action ownership which allows channel managers to update actions in other channels via the channel action update endpo…","severity":"medium","cvss":5,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L","cwe":["CWE-639"],"vendor":"Mattermost","product":"Mattermost","affected":["Mattermost >= 11.9.0 <= 11.9.0","Mattermost >= 11.8.0 <= 11.8.4","Mattermost >= 11.7.0 <= 11.7.7","Mattermost >= 10.11.0 <= 10.11.22"],"published":"2026-09-14","updated":"2026-09-16","sourceUpdated":"2026-09-16T19:30:49.967","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-10542","references":[{"url":"https://mattermost.com/security-updates","label":"responsibledisclosure@mattermost.com"}],"tags":["nvd","cve.org"],"epss":0.00129,"epssPercentile":0.02092,"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-09-14T11:02:43.768854Z"},"ingestedAt":"2026-09-14T15:23:07.462Z","slug":"CVE-2026-10542","body":"## Overview\n\nMattermost versions 11.9.x <= 11.9.0, 11.8.x <= 11.8.4, 11.7.x <= 11.7.7, 10.11.x <= 10.11.22 fail to validate channel action ownership which allows channel managers to update actions in other channels via the channel action update endpoint.. Mattermost Advisory ID: MMSA-2026-00692\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":28,"depthScoreParts":{"impact":27.5,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}