{"action":"Upgrade moodle/moodle to 4.0.0 or later.","affected":[{"fixed":"4.0.0","introduced":"3.0.0"}],"component":"moodle/moodle","cve_ids":["CVE-2025-53021"],"ecosystem":"Packagist","epss":0.00325,"exploited":false,"fixed_versions":["4.0.0"],"ghsa_id":"GHSA-cgvv-3455-824j","id":"tcs_01M5KF0ZJ7P9D5FNJEGS6CBVHN","modified_at":"2025-07-10T06:27:06.869610Z","published_at":"2025-06-24T21:30:29Z","references":["https://osv.dev/vulnerability/GHSA-cgvv-3455-824j","https://nvd.nist.gov/vuln/detail/CVE-2025-53021","https://github.com/moodle/moodle","https://github.com/moodle/moodle/releases/tag/v3.11.18","https://moodledev.io/general/releases#moodle-311","https://rentry.co/moodle-oauth2-cve"],"severity":{"label":"medium","score":4.2},"sources":[{"source":"osv","source_id":"GHSA-cgvv-3455-824j","url":"https://osv.dev/vulnerability/GHSA-cgvv-3455-824j"}],"summary":"Moodle Session Fixation allows unauthenticated users to hijack sessions via sesskey parameter"}