{"id":"CVE-2017-18903","aliases":["GHSA-fcwg-45jh-5qhf","GO-2026-4305"],"url":"https://o3.security/vulnerability/CVE-2017-18903","summary":"Mattermost Server vulnerable to CSRF if CORS is enabled","details":"An issue was discovered in Mattermost Server before 4.0.0, 3.10.2, and 3.9.2. CSRF can occur if CORS is enabled.","published":"2020-06-19T19:15:11.717Z","modified":"2026-07-31T18:31:22.633642471Z","cvss":{"score":8.8,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H"},"epss":{"score":0.00424,"percentile":0.35629,"asOf":"2026-09-08"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Go","name":"github.com/mattermost/mattermost-server","fixedVersion":"3.9.2"},{"ecosystem":"Go","name":"github.com/mattermost/mattermost-server","fixedVersion":"3.10.2"}],"fix":{"url":"https://github.com/mattermost/mattermost/commit/312269ad0bd166174f07f9df7391fce714601600","label":"mattermost/mattermost@312269a"},"references":[{"type":"ADVISORY","url":"https://mattermost.com/security-updates/"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2017-18903"},{"type":"WEB","url":"https://github.com/mattermost/mattermost/commit/312269ad0bd166174f07f9df7391fce714601600"},{"type":"WEB","url":"https://github.com/mattermost/mattermost/commit/4519b03d95e8bfe1b2f74094673ae1a2f39f6b47"},{"type":"WEB","url":"https://github.com/mattermost/mattermost/commit/a18479df0940be8503c9b88993490741793eba9e"},{"type":"PACKAGE","url":"https://github.com/mattermost/mattermost"},{"type":"WEB","url":"https://mattermost.com/security-updates"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-07-31T18:31:22.633642471Z"}}