{"id":"CVE-2023-6202","aliases":["GHSA-85jj-c9jr-9jhx"],"title":"Mattermost Improper Access Control vulnerability","summary":"Mattermost Improper Access Control vulnerability","severity":"medium","cvss":4.3,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N","vendor":"mattermost","product":"github.com/mattermost/mattermost/server/v8","ecosystem":"go","affected":["github.com/mattermost/mattermost/server/v8 >= 9.1.0, < 9.1.1","github.com/mattermost/mattermost/server/v8 >= 9.0.0, < 9.0.2","github.com/mattermost/mattermost/server/v8 < 8.1.4","github.com/mattermost/mattermost-server/v6 < 7.8.13"],"patched":["github.com/mattermost/mattermost/server/v8 9.1.1","github.com/mattermost/mattermost/server/v8 9.0.2","github.com/mattermost/mattermost/server/v8 8.1.4","github.com/mattermost/mattermost-server/v6 7.8.13"],"published":"2023-11-27","updated":"2026-09-10","sourceUpdated":"2026-09-10T03:49:58.905302619Z","source":"OSV","sourceUrl":"https://osv.dev/vulnerability/GHSA-85jj-c9jr-9jhx","references":[{"url":"https://nvd.nist.gov/vuln/detail/CVE-2023-6202"},{"url":"https://github.com/mattermost/mattermost"},{"url":"https://mattermost.com/security-updates"}],"tags":["osv","go"],"epss":0.00443,"epssPercentile":0.37938,"ingestedAt":"2026-09-12T03:13:01.766Z","slug":"CVE-2023-6202","body":"## Overview\n\nMattermost fails to perform proper authorization in the `/plugins/focalboard/api/v2/users` endpoint allowing an attacker who is a guest user and knows the ID of another user to get their information (e.g. name, surname, nickname) via Mattermost Boards.\n\n\n\n## Affected packages\n\n- `github.com/mattermost/mattermost/server/v8 >= 9.1.0, < 9.1.1`\n- `github.com/mattermost/mattermost/server/v8 >= 9.0.0, < 9.0.2`\n- `github.com/mattermost/mattermost/server/v8 < 8.1.4`\n- `github.com/mattermost/mattermost-server/v6 < 7.8.13`\n\n## Remediation\n\nUpgrade to a patched release:\n\n- `github.com/mattermost/mattermost/server/v8 9.1.1`\n- `github.com/mattermost/mattermost/server/v8 9.0.2`\n- `github.com/mattermost/mattermost/server/v8 8.1.4`\n- `github.com/mattermost/mattermost-server/v6 7.8.13`","depth":"sunlit","depthScore":24,"depthScoreParts":{"impact":23.7,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}