{"id":"CVE-2017-18872","aliases":["GHSA-hgrp-fgm8-56g8","GO-2025-4075"],"url":"https://o3.security/vulnerability/CVE-2017-18872","summary":"Mattermost Server's OAuth 2.0 service is vulnerable to attack through Missing Authorization","details":"An issue was discovered in Mattermost Server before 4.4.3 and 4.3.3. Attackers could reconfigure an OAuth app in some cases where Mattermost is an OAuth 2.0 service provider.","published":"2020-06-19T18:15:10.537Z","modified":"2026-10-24T10:30:44.395319057Z","cvss":{"score":4.3,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N"},"epss":{"score":0.00565,"percentile":0.44333,"asOf":"2026-08-23"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Go","name":"github.com/mattermost/mattermost-server","fixedVersion":"4.3.3"},{"ecosystem":"Go","name":"github.com/mattermost/mattermost-server","fixedVersion":"4.4.3"}],"fix":{"url":"https://github.com/mattermost/mattermost/commit/8f6bb1570dd234c63de5241eff9fbb268aad358c","label":"mattermost/mattermost@8f6bb15"},"references":[{"type":"ADVISORY","url":"https://mattermost.com/security-updates/"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2017-18872"},{"type":"WEB","url":"https://github.com/mattermost/mattermost/commit/8f6bb1570dd234c63de5241eff9fbb268aad358c"},{"type":"PACKAGE","url":"https://github.com/mattermost/mattermost"},{"type":"WEB","url":"https://mattermost.com/security-updates"},{"type":"WEB","url":"http://github.com/mattermost/mattermost/commit/753386c2b2b06233d8bd977e3db29a4fe18098cb"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-10-24T10:30:44.395319057Z"}}