{"id":"CVE-2021-42567","aliases":["EUVD-2021-2521","GHSA-gfhx-jjwq-63gv"],"status":"published","title":"Cross-site Scripting in Apereo CAS","description":"Apereo CAS through 6.4.1 allows XSS via POST requests sent to the REST API endpoints.","severity":{"version":"3.1","score":6.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","level":"medium","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-10","score":0.08191,"percentile":0.94916,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-79"],"published":"2021-12-07T21:10:49Z","modified":"2026-10-20T10:55:00Z","exploits":[{"source":"nuclei","id":"CVE-2021-42567","title":"Apereo CAS Cross-Site Scripting","type":"detection 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