{"action":"Upgrade github.com/mattermost/mattermost/server/v8 to 8.0.0-20260123211116-9efe617be8b8 or later.","affected":[{"fixed":"8.0.0-20260123211116-9efe617be8b8","introduced":"0"}],"component":"github.com/mattermost/mattermost/server/v8","cve_ids":["CVE-2026-2457"],"ecosystem":"Go","epss":0.00111,"exploited":false,"fixed_versions":["8.0.0-20260123211116-9efe617be8b8"],"ghsa_id":"GHSA-ph22-fw5m-w2q9","id":"tcs_01M5KGFNCQ4KV9ZYF1M6RTH9G8","modified_at":"2026-03-23T18:45:15.192153Z","published_at":"2026-03-23T18:14:47Z","references":["https://osv.dev/vulnerability/GO-2026-4732","https://github.com/advisories/GHSA-ph22-fw5m-w2q9","https://nvd.nist.gov/vuln/detail/CVE-2026-2457","https://github.com/mattermost/mattermost/commit/9efe617be8b8f1d036e12721e8e73b69a543ed34","https://mattermost.com/security-updates"],"severity":{"label":"medium","score":4.3},"sources":[{"source":"osv","source_id":"GO-2026-4732#Go/github.com/mattermost/mattermost/server/v8","url":"https://osv.dev/vulnerability/GO-2026-4732"},{"source":"nvd","source_id":"CVE-2026-2457","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-2457"}],"summary":"Mattermost allows attackers to spoof permalink embeds in github.com/mattermost/mattermost-server"}