{"id":"CVE-2021-36403","aliases":["BIT-moodle-2021-36403","GHSA-j9cw-5cpj-9qj5"],"url":"https://o3.security/vulnerability/CVE-2021-36403","summary":"Moodle has a Hidden Functionality vulnerability","details":"In Moodle, in some circumstances, email notifications of messages could have the link back to the original message hidden by HTML, which may pose a phishing risk.","published":"2023-03-06T23:15:10.540Z","modified":"2026-10-24T10:30:19.419535622Z","cvss":{"score":5.3,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N"},"epss":{"score":0.00526,"percentile":0.42303,"asOf":"2026-08-23"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Packagist","name":"moodle/moodle","fixedVersion":"3.11.1"},{"ecosystem":"Packagist","name":"moodle/moodle","fixedVersion":"3.10.5"},{"ecosystem":"Packagist","name":"moodle/moodle","fixedVersion":"3.9.8"}],"fix":null,"references":[{"type":"FIX","url":"https://moodle.org/mod/forum/discuss.php?d=424809"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2021-36403"},{"type":"PACKAGE","url":"https://github.com/moodle/moodle"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-10-24T10:30:19.419535622Z"}}