{"id":"CVE-2026-7387","aliases":["GHSA-6hxm-w4hv-vgvw"],"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":"2026-08-25T00:55:56.098554613Z","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":0.23094,"asOf":"2026-08-24"},"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":null,"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"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-25T00:55:56.098554613Z"}}