{"id":"CVE-2021-21673","aliases":["GHSA-2vvr-5757-qp87"],"url":"https://o3.security/vulnerability/CVE-2021-21673","summary":"Open redirect vulnerability in Jenkins CAS Plugin","details":"Jenkins CAS Plugin 1.6.0 and earlier improperly determines that a redirect URL after login is legitimately pointing to Jenkins.\n\nThis allows attackers to perform phishing attacks by having users go to a Jenkins URL that will forward them to a different site after successful authentication.\n\nJenkins CAS Plugin 1.6.1 only redirects to relative (Jenkins) URLs.","published":"2021-06-30T17:15:09.160Z","modified":"2026-10-24T10:30:27.597389670Z","cvss":{"score":6.1,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Maven","name":"org.jenkins-ci.plugins:cas-plugin","fixedVersion":"1.6.1"}],"fix":{"url":"https://github.com/jenkinsci/cas-plugin/commit/8ac536a953156160dbabb61bdb3b9bc75c3d0ef9","label":"jenkinsci/cas-plugin@8ac536a"},"references":[{"type":"ADVISORY","url":"http://www.openwall.com/lists/oss-security/2021/06/30/1"},{"type":"ADVISORY","url":"https://www.jenkins.io/security/advisory/2021-06-30/#SECURITY-2387"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2021-21673"},{"type":"WEB","url":"https://github.com/jenkinsci/cas-plugin/commit/8ac536a953156160dbabb61bdb3b9bc75c3d0ef9"},{"type":"PACKAGE","url":"https://github.com/jenkinsci/cas-plugin"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-10-24T10:30:27.597389670Z"}}