{"id":"CVE-2026-10542","aliases":["EUVD-2026-77366","GHSA-462g-wr4w-p54m"],"status":"published","title":"Playbooks channel action update validation issue","description":"Mattermost versions 11.9.x \u003c= 11.9.0, 11.8.x \u003c= 11.8.4, 11.7.x \u003c= 11.7.7, 10.11.x \u003c= 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","severity":{"version":"3.1","score":5,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-12","score":0.00119,"percentile":0.01785,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-639"],"published":"2026-09-14T10:37:32Z","modified":"2026-10-28T02:30:53Z","products":[{"vendor":"mattermost","product":"mattermost"},{"vendor":"mattermost","product":"mattermost_server"}],"references":[{"url":"https://mattermost.com/security-updates","tags":["vendor-advisory","Vendor Advisory","advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-10542","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-462g-wr4w-p54m"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/10xxx/CVE-2026-10542.json","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2026-10542","title":"Playbooks channel action update validation issue","description":"Mattermost versions 11.9.x \u003c= 11.9.0, 11.8.x \u003c= 11.8.4, 11.7.x \u003c= 11.7.7, 10.11.x \u003c= 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","status":"published","published":"2026-09-14T10:37:32.147Z","modified":"2026-09-14T11:19:45.549Z","cvss":[{"version":"3.1","score":5,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L","level":"medium","assessor":"cna"}],"cwes":["CWE-639"],"updated_at":"2026-11-02T13:40:01.309549Z"}],"euvd":[{"id":"EUVD-2026-77366","description":"Mattermost versions 11.9.x \u003c= 11.9.0, 11.8.x \u003c= 11.8.4, 11.7.x \u003c= 11.7.7, 10.11.x \u003c= 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","status":"published","published":"2026-09-14T10:37:32Z","modified":"2026-09-14T11:19:45Z","cvss":[{"version":"3.1","score":5,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L","level":"medium"}],"updated_at":"2026-11-02T17:28:21.556158Z"}],"ghsa":[{"id":"GHSA-462g-wr4w-p54m","title":"Mattermost versions 11.9.x \u003c= 11.9.0, 11.8.x \u003c= 11.8.4, 11.7.x \u003c= 11.7.7, 10.11.x \u003c= 10.11.22...","description":"Mattermost versions 11.9.x \u003c= 11.9.0, 11.8.x \u003c= 11.8.4, 11.7.x \u003c= 11.7.7, 10.11.x \u003c= 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","status":"published","published":"2026-09-14T12:31:37Z","modified":"2026-09-14T12:31:43Z","cvss":[{"version":"3.1","score":5,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L","level":"medium"}],"cwes":["CWE-639"],"updated_at":"2026-11-02T15:11:49.397809Z"}],"nvd":[{"id":"CVE-2026-10542","description":"Mattermost versions 11.9.x \u003c= 11.9.0, 11.8.x \u003c= 11.8.4, 11.7.x \u003c= 11.7.7, 10.11.x \u003c= 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","status":"published","published":"2026-09-14T11:17:02.447Z","modified":"2026-10-07T16:32:30.77Z","cvss":[{"version":"3.1","score":5,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L","level":"medium","assessor":"secondary"},{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N","level":"medium","assessor":"primary"}],"cwes":["CWE-639"],"updated_at":"2026-11-02T14:12:46.980627Z"}],"osv":[{"id":"CVE-2026-10542","title":"Playbooks channel action update validation issue","description":"Mattermost versions 11.9.x \u003c= 11.9.0, 11.8.x \u003c= 11.8.4, 11.7.x \u003c= 11.7.7, 10.11.x \u003c= 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","status":"published","published":"2026-09-14T10:37:32.147Z","modified":"2026-10-28T02:30:53.673068063Z","cvss":[{"version":"3.1","score":5,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L","level":"medium"}],"cwes":["CWE-639"],"updated_at":"2026-11-02T15:44:54.583213Z"}]}}