{"id":"CVE-2026-13417","aliases":["EUVD-2026-77376","GHSA-mq74-c6v5-598g"],"status":"published","title":"Boards plugin denial of service via unvalidated block fields.properties","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 the type of `fields.properties` on block creation which allows an authenticated user with editor access to a board to crash the Boards plugin worker and trigger a denial of service via a child block whose `fields.properties` is a non-object value. Mattermost Advisory ID: MMSA-2026-00710","severity":{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.00367,"percentile":0.30957,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-754"],"published":"2026-09-14T10:44:59Z","modified":"2026-10-28T02:30:43Z","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-2026-13417","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-mq74-c6v5-598g"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/13xxx/CVE-2026-13417.json","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2026-13417","title":"Boards plugin denial of service via unvalidated block fields.properties","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 the type of `fields.properties` on block creation which allows an authenticated user with editor access to a board to crash the Boards plugin worker and trigger a denial of service via a child block whose `fields.properties` is a non-object value. Mattermost Advisory ID: MMSA-2026-00710","status":"published","published":"2026-09-14T10:44:59.391Z","modified":"2026-09-14T11:19:44.392Z","cvss":[{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L","level":"medium","assessor":"cna"}],"cwes":["CWE-754"],"updated_at":"2026-11-02T14:19:49.885652Z"}],"euvd":[{"id":"EUVD-2026-77376","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 the type of `fields.properties` on block creation which allows an authenticated user with editor access to a board to crash the Boards plugin worker and trigger a denial of service via a child block whose `fields.properties` is a non-object value. Mattermost Advisory ID: MMSA-2026-00710","status":"published","published":"2026-09-14T10:44:59Z","modified":"2026-09-14T11:19:44Z","cvss":[{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L","level":"medium"}],"updated_at":"2026-11-02T17:28:21.556158Z"}],"ghsa":[{"id":"GHSA-mq74-c6v5-598g","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 the type of `fields.properties` on block creation which allows an authenticated user with editor access to a board to crash the Boards plugin worker and trigger a denial of service via a child block whose `fields.properties` is a non-object value. Mattermost Advisory ID: MMSA-2026-00710","status":"published","published":"2026-09-14T12:31:37Z","modified":"2026-09-14T12:31:44Z","cvss":[{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L","level":"medium"}],"cwes":["CWE-754"],"updated_at":"2026-11-02T15:11:49.397809Z"}],"nvd":[{"id":"CVE-2026-13417","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 the type of `fields.properties` on block creation which allows an authenticated user with editor access to a board to crash the Boards plugin worker and trigger a denial of service via a child block whose `fields.properties` is a non-object value. Mattermost Advisory ID: MMSA-2026-00710","status":"published","published":"2026-09-14T11:17:03.18Z","modified":"2026-10-07T16:17:21.987Z","cvss":[{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L","level":"medium","assessor":"secondary"}],"cwes":["CWE-754"],"updated_at":"2026-11-02T14:12:46.980627Z"}],"osv":[{"id":"CVE-2026-13417","title":"Boards plugin denial of service via unvalidated block fields.properties","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 the type of `fields.properties` on block creation which allows an authenticated user with editor access to a board to crash the Boards plugin worker and trigger a denial of service via a child block whose `fields.properties` is a non-object value. Mattermost Advisory ID: MMSA-2026-00710","status":"published","published":"2026-09-14T10:44:59.391Z","modified":"2026-10-28T02:30:43.688453074Z","cvss":[{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L","level":"medium"}],"cwes":["CWE-754"],"updated_at":"2026-11-02T15:44:57.354194Z"}]}}