{"id":"CVE-2025-49222","aliases":["GHSA-q453-638c-h4mr","GO-2025-3904"],"url":"https://o3.security/vulnerability/CVE-2025-49222","summary":"Mattermost Shared Channel Upload Type Validation Bypass","details":"Mattermost versions 10.8.x <= 10.8.3, 10.5.x <= 10.5.8, 9.11.x <= 9.11.17, 10.9.x <= 10.9.2, 10.10.x <= 10.10.0 fail to validate upload types in remote cluster upload sessions which allows a system admin to upload non-attachment file types via shared channels that could potentially be placed in arbitrary filesystem directories.","published":"2025-08-21T07:59:45.057Z","modified":"2026-09-18T03:45:24.918809560Z","cvss":{"score":6.8,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:N/A:N"},"epss":{"score":0.00301,"percentile":0.22697,"asOf":"2026-08-18"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Go","name":"github.com/mattermost/mattermost-server","fixedVersion":"10.8.4"},{"ecosystem":"Go","name":"github.com/mattermost/mattermost-server","fixedVersion":"10.5.9"},{"ecosystem":"Go","name":"github.com/mattermost/mattermost-server","fixedVersion":"9.11.18"},{"ecosystem":"Go","name":"github.com/mattermost/mattermost-server","fixedVersion":"10.9.3"},{"ecosystem":"Go","name":"github.com/mattermost/mattermost-server","fixedVersion":"10.10.1"},{"ecosystem":"Go","name":"github.com/mattermost/mattermost/server/v8","fixedVersion":"8.0.0-20250708173752-d6b35c41f0ae5"},{"ecosystem":"Go","name":"github.com/mattermost/mattermost-server/v5","fixedVersion":null},{"ecosystem":"Go","name":"github.com/mattermost/mattermost-server/v6","fixedVersion":null}],"fix":null,"references":[{"type":"WEB","url":"https://mattermost.com/security-updates"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/49xxx/CVE-2025-49222.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-49222"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-09-18T03:45:24.918809560Z"}}