{"action":"Upgrade github.com/mattermost/mattermost-server to 4.3.0+incompatible or later.","affected":[{"fixed":"4.3.0+incompatible","introduced":"4.3.0-rc1+incompatible"}],"component":"github.com/mattermost/mattermost-server","cve_ids":["CVE-2017-18878"],"ecosystem":"Go","epss":0.00777,"exploited":false,"fixed_versions":["4.3.0+incompatible"],"ghsa_id":"GHSA-h564-6gc2-fcc6","id":"tcs_01M5KGC6CJ95SVAGD47G9EQC4W","modified_at":"2025-12-15T21:11:13.725259Z","published_at":"2025-12-15T20:33:49Z","references":["https://osv.dev/vulnerability/GO-2025-4191","https://github.com/advisories/GHSA-h564-6gc2-fcc6","https://nvd.nist.gov/vuln/detail/CVE-2017-18878","https://github.com/mattermost/mattermost/commit/6be8113eb60cf5ddd2dc1c3f4db05cae0c183086","https://github.com/mattermost/mattermost/commit/8fbbd688ea2466dd0d70e9c07e9703d78f8a19a5","https://github.com/mattermost/mattermost/commit/affd35071ea155069979fd359726296de8aa6aaf","https://mattermost.com/security-updates"],"severity":{"label":"unknown"},"sources":[{"source":"osv","source_id":"GO-2025-4191","url":"https://osv.dev/vulnerability/GO-2025-4191"}],"summary":"Mattermost Server allows users with a session ID to revoke another users' session in github.com/mattermost/mattermost-server"}