{"action":"Upgrade github.com/mattermost/mattermost/server/v8 to 8.0.0-20260407102538-faa7d75b4ea0 or later.","affected":[{"fixed":"8.0.0-20260407102538-faa7d75b4ea0","introduced":"0"}],"component":"github.com/mattermost/mattermost/server/v8","cve_ids":["CVE-2026-4915"],"ecosystem":"Go","epss":0.00277,"exploited":false,"fixed_versions":["8.0.0-20260407102538-faa7d75b4ea0"],"ghsa_id":"GHSA-5gmf-x7hg-97wf","id":"tcs_01M5KEYAY86V1TPRZWVHX48GF5","modified_at":"2026-07-07T16:11:26.107537868Z","published_at":"2026-05-26T13:30:40Z","references":["https://osv.dev/vulnerability/GHSA-5gmf-x7hg-97wf","https://nvd.nist.gov/vuln/detail/CVE-2026-4915","https://github.com/mattermost/mattermost/commit/faa7d75b4ea041701e97948f8aa1332e3626a39a","https://github.com/mattermost/mattermost","https://mattermost.com/security-updates"],"severity":{"label":"medium","score":6.5},"sources":[{"source":"osv","source_id":"GHSA-5gmf-x7hg-97wf#Go/github.com/mattermost/mattermost/server/v8","url":"https://osv.dev/vulnerability/GHSA-5gmf-x7hg-97wf"}],"summary":"Mattermost doesn't filter nil elements from outgoing webhook attachment payloads before processing"}