{"action":"Upgrade github.com/mattermost/mattermost-server to 10.11.15 or later.","affected":[{"fixed":"11.6.1","introduced":"11.6.0"},{"fixed":"11.5.4","introduced":"11.5.0"},{"fixed":"11.4.5","introduced":"11.4.0"},{"fixed":"10.11.15","introduced":"10.11.0"}],"component":"github.com/mattermost/mattermost-server","cve_ids":["CVE-2026-4858"],"ecosystem":"Go","epss":0.00327,"exploited":false,"fixed_versions":["11.6.1","11.5.4","11.4.5","10.11.15"],"ghsa_id":"GHSA-c4r7-j7pp-r8mp","id":"tcs_01M5KF6PVG9NYH5NTVD3GKNHDR","modified_at":"2026-06-25T19:56:31.636644526Z","published_at":"2026-05-21T09:32:12Z","references":["https://osv.dev/vulnerability/GHSA-c4r7-j7pp-r8mp","https://nvd.nist.gov/vuln/detail/CVE-2026-4858","https://github.com/mattermost/mattermost","https://mattermost.com/security-updates"],"severity":{"label":"high","score":8},"sources":[{"source":"osv","source_id":"GHSA-c4r7-j7pp-r8mp","url":"https://osv.dev/vulnerability/GHSA-c4r7-j7pp-r8mp"}],"summary":"Mattermost has a Path Traversal issue"}