{"id":"CVE-2025-12419","aliases":["GHSA-3x39-62h4-f8j6","GO-2025-4168"],"url":"https://o3.security/vulnerability/CVE-2025-12419","summary":"Account takeover on OAuth/OpenID-enabled servers","details":"Mattermost versions 10.12.x <= 10.12.1, 10.11.x <= 10.11.4, 10.5.x <= 10.5.12, 11.0.x <= 11.0.3 fail to properly validate OAuth state tokens during OpenID Connect authentication which allows an authenticated attacker with team creation privileges to take over a user account via manipulation of authentication data during the OAuth completion flow. This requires email verification to be disabled (default: disabled), OAuth/OpenID Connect to be enabled, and the attacker to control two users in the SSO system with one of them never having logged into Mattermost.","published":"2025-11-27T15:55:44.815Z","modified":"2026-09-18T03:45:23.500557089Z","cvss":{"score":9.9,"severity":"CRITICAL","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H"},"epss":{"score":0.00342,"percentile":0.26727,"asOf":"2026-08-24"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Go","name":"github.com/mattermost/mattermost/server/v8","fixedVersion":"8.0.0-20251028000919-d3ed703dc833"},{"ecosystem":"Go","name":"github.com/mattermost/mattermost-server","fixedVersion":"10.12.2"},{"ecosystem":"Go","name":"github.com/mattermost/mattermost-server","fixedVersion":"10.11.5"},{"ecosystem":"Go","name":"github.com/mattermost/mattermost-server","fixedVersion":"10.5.13"},{"ecosystem":"Go","name":"github.com/mattermost/mattermost-server","fixedVersion":"11.0.4"}],"fix":{"url":"https://github.com/mattermost/mattermost/pull/34296","label":"mattermost/mattermost#34296"},"references":[{"type":"WEB","url":"https://mattermost.com/security-updates"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/12xxx/CVE-2025-12419.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-12419"},{"type":"WEB","url":"https://github.com/mattermost/mattermost/pull/34296"},{"type":"WEB","url":"https://github.com/mattermost/mattermost/commit/15364790cc277cfaa372693d2d5442b87f70fd42"},{"type":"WEB","url":"https://github.com/mattermost/mattermost/commit/364c2203de00fe0d8424b6b46d6f0eeb02a2539a"},{"type":"WEB","url":"https://github.com/mattermost/mattermost/commit/46b5c436bb3093cc1da3fa2455f93d4c52389eee"},{"type":"WEB","url":"https://github.com/mattermost/mattermost/commit/c3f4818afe46a7084740e809708ae22641c76d8d"},{"type":"WEB","url":"https://github.com/mattermost/mattermost/commit/d3ed703dc8330684952eb8d49a375bac6ea7b0c6"},{"type":"ADVISORY","url":"https://github.com/advisories/GHSA-3x39-62h4-f8j6"},{"type":"PACKAGE","url":"https://github.com/mattermost/mattermost"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-09-18T03:45:23.500557089Z"}}