{"id":"CVE-2026-7387","aliases":["GHSA-6hxm-w4hv-vgvw","GO-2026-6280"],"url":"https://o3.security/vulnerability/CVE-2026-7387","summary":"Mattermost group syncable endpoints allow privilege escalation via scheme_admin","details":"Mattermost versions 11.6.x <= 11.6.1, 11.5.x <= 11.5.4, 10.11.x <= 10.11.15, 10.11.x <= 10.11.16 Mattermost fails to require role-management authorization when setting the scheme_admin flag on group syncable link and patch endpoints, which allows a user with group-link permissions to escalate themselves and group members to team or channel admin via crafted API requests.. Mattermost Advisory ID: MMSA-2026-00665","published":"2026-06-12T15:54:10.103Z","modified":"2026-09-29T18:26:42.569483704Z","cvss":{"score":8.8,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"},"epss":{"score":0.0031,"percentile":0.23855,"asOf":"2026-09-17"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Go","name":"github.com/mattermost/mattermost-server","fixedVersion":"11.6.1"},{"ecosystem":"Go","name":"github.com/mattermost/mattermost-server","fixedVersion":"11.5.5"},{"ecosystem":"Go","name":"github.com/mattermost/mattermost-server","fixedVersion":"10.11.17"},{"ecosystem":"Go","name":"github.com/mattermost/mattermost/server/v8","fixedVersion":"8.0.0-20260506065351-202d125afa87"}],"fix":{"url":"https://github.com/mattermost/mattermost/pull/36434","label":"mattermost/mattermost#36434"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/7xxx/CVE-2026-7387.json"},{"type":"ADVISORY","url":"https://mattermost.com/security-updates"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-7387"},{"type":"WEB","url":"https://github.com/mattermost/mattermost/pull/36434"},{"type":"WEB","url":"https://github.com/mattermost/mattermost/pull/36432"},{"type":"WEB","url":"https://github.com/mattermost/mattermost/pull/36431"},{"type":"WEB","url":"https://github.com/mattermost/mattermost/pull/36423"},{"type":"WEB","url":"https://github.com/mattermost/mattermost/pull/36316"},{"type":"WEB","url":"https://github.com/mattermost/mattermost/commit/d5f29c8ebbeb04460d16d9e2635ce50deeb78428"},{"type":"WEB","url":"https://github.com/mattermost/mattermost/commit/a9e574a82633915f22071f0d7ca2b006f249ec2a"},{"type":"WEB","url":"https://github.com/mattermost/mattermost/commit/8c72083414e675c97987374395e36d1f36b4bd8a"},{"type":"WEB","url":"https://github.com/mattermost/mattermost/commit/202d125afa87fe39611686850fd82590c99ca344"},{"type":"WEB","url":"https://github.com/mattermost/mattermost/commit/1ce2484a00c9821ee19708d2c46720e4855033a9"},{"type":"WEB","url":"https://github.com/mattermost/mattermost/releases/tag/v10.11.16"},{"type":"WEB","url":"https://github.com/mattermost/mattermost/releases/tag/v11.5.5"},{"type":"WEB","url":"https://github.com/mattermost/mattermost/releases/tag/v11.6.2"},{"type":"WEB","url":"https://github.com/mattermost/mattermost/releases/tag/v11.7.0"},{"type":"PACKAGE","url":"https://github.com/mattermost/mattermost"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-09-29T18:26:42.569483704Z"}}