{"action":"Upgrade github.com/mattermost/mattermost-server to 5.3.2-0.20260123211116-9efe617be8b8 or later.","affected":[{"fixed":"5.3.2-0.20260123211116-9efe617be8b8","introduced":"0"},{"fixed":"10.11.11","introduced":"10.11.0-rc1"},{"fixed":"11.2.3","introduced":"11.2.0-rc1"},{"fixed":"11.3.1","introduced":"11.3.0-rc1"}],"component":"github.com/mattermost/mattermost-server","cve_ids":["CVE-2026-2457"],"ecosystem":"Go","epss":0.00109,"exploited":false,"fixed_versions":["5.3.2-0.20260123211116-9efe617be8b8","10.11.11","11.2.3","11.3.1"],"ghsa_id":"GHSA-ph22-fw5m-w2q9","id":"tcs_01M5KFHD0Z2SXRPC1EEJ0Q4J23","modified_at":"2026-03-23T18:56:18.286997Z","published_at":"2026-03-16T15:30:42Z","references":["https://osv.dev/vulnerability/GHSA-ph22-fw5m-w2q9","https://nvd.nist.gov/vuln/detail/CVE-2026-2457","https://github.com/mattermost/mattermost/commit/9efe617be8b8f1d036e12721e8e73b69a543ed34","https://github.com/mattermost/mattermost","https://mattermost.com/security-updates"],"severity":{"label":"medium","score":4.3},"sources":[{"source":"osv","source_id":"GHSA-ph22-fw5m-w2q9#Go/github.com/mattermost/mattermost-server","url":"https://osv.dev/vulnerability/GHSA-ph22-fw5m-w2q9"}],"summary":"Mattermost allows attackers to spoof permalink embeds"}