{"id":"CVE-2026-6739","summary":"Mattermost: Delegated admins could patch protected default system roles","details":"Mattermost versions 11.6.x \u003c= 11.6.1, 11.5.x \u003c= 11.5.4, 10.11.x \u003c= 10.11.15, 10.11.x \u003c= 10.11.16 fail to require system-level permission when patching protected default system roles, which allows authenticated users with delegated user-management permissions to escalate privileges by altering built-in role permissions via the role patch API.. Mattermost Advisory ID: MMSA-2026-00656","modified":"2026-07-15T01:48:55.953003737Z","published":"2026-06-12T15:49:14.444Z","database_specific":{"cna_assigner":"Mattermost","cwe_ids":["CWE-863"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/6xxx/CVE-2026-6739.json","unresolved_ranges":[{"extracted_events":[{"introduced":"11.6.0"},{"last_affected":"11.6.1"},{"introduced":"11.5.0"},{"last_affected":"11.5.4"},{"introduced":"10.11.0"},{"last_affected":"10.11.15"},{"introduced":"10.11.0"},{"last_affected":"10.11.16"}],"source":"AFFECTED_FIELD"}]},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/6xxx/CVE-2026-6739.json"},{"type":"ADVISORY","url":"https://mattermost.com/security-updates"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-6739"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/mattermost/mattermost","events":[{"introduced":"5b955468ea1ea8b56c0fb10feb258a36a767d7bb"},{"fixed":"202d125afa87fe39611686850fd82590c99ca344"},{"introduced":"9f2616376582893035a7e3cb38b0fab648bba4e8"},{"fixed":"d5f29c8ebbeb04460d16d9e2635ce50deeb78428"},{"introduced":"d4f4e78835e86e2e76f76bfe797623076f5c9835"},{"fixed":"1ce2484a00c9821ee19708d2c46720e4855033a9"}],"database_specific":{"cpe":"cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*","extracted_events":[{"introduced":"10.11.0"},{"fixed":"10.11.17"},{"introduced":"11.5.0"},{"fixed":"11.5.5"},{"introduced":"11.6.0"},{"fixed":"11.6.2"}],"source":"CPE_RANGE"}}],"versions":["v10.11.15-rc1","v10.11.15","v11.5.4","v11.6.1-rc1","v11.6.1","v11.5.3","v10.11.14","v11.5.2-rc3","v11.5.2","v11.6.0","v10.11.14-rc1","v11.5.0","v11.5.2-rc2","v11.5.2-rc1","v10.11.13","v11.5.1","v10.11.13-rc1","v10.11.12","v10.11.11-rc2","v10.11.11","v10.11.11-rc1","v10.11.10","v10.11.9","v10.11.9-rc1","v10.11.8","v10.11.7","v10.11.6","v10.11.5","v10.11.4-rc3","v10.11.4","v10.11.4-rc2","v10.11.4-rc1","v10.11.3","v10.11.2-rc2","v10.11.2","v10.11.2-rc1","v10.11.1","v10.11.1-rc1","v10.11.0-rc3","v10.11.0","mattermost-redux@10.11.0","@mattermost/types@10.11.0","@mattermost/client@10.11.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-6739.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:L"}]}