{"id":"CVE-2021-33829","aliases":["BIT-drupal-2021-33829","DRUPAL-CORE-2021-003","GHSA-rgx6-rjj4-c388"],"url":"https://o3.security/vulnerability/CVE-2021-33829","summary":"ckeditor4 vulnerable to cross-site scripting","details":"A cross-site scripting (XSS) vulnerability in the HTML Data Processor in CKEditor 4 4.14.0 through 4.16.x before 4.16.1 allows remote attackers to inject executable JavaScript code through a crafted comment because --!> is mishandled.","published":"2021-06-09T12:15:07.863Z","modified":"2026-07-08T06:00:39.834447918Z","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":null,"affectedPackages":[{"ecosystem":"npm","name":"ckeditor4","fixedVersion":"4.16.1"},{"ecosystem":"Packagist","name":"drupal/core","fixedVersion":"7.80"},{"ecosystem":"Packagist","name":"drupal/core","fixedVersion":"8.9.16"},{"ecosystem":"Packagist","name":"drupal/core","fixedVersion":"9.0.14"},{"ecosystem":"Packagist","name":"drupal/core","fixedVersion":"9.1.9"},{"ecosystem":"Packagist","name":"drupal/drupal","fixedVersion":"7.80"},{"ecosystem":"Packagist","name":"drupal/drupal","fixedVersion":"8.9.16"},{"ecosystem":"Packagist","name":"drupal/drupal","fixedVersion":"9.0.14"},{"ecosystem":"Packagist","name":"drupal/drupal","fixedVersion":"9.1.9"}],"fix":null,"references":[{"type":"WEB","url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NYA354LJP47KCVJMTUO77ZCX3ZK42G3T/"},{"type":"WEB","url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/UVOYN2WKDPLKCNILIGEZM236ABQASLGW/"},{"type":"WEB","url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WAGNWHFIQAVCP537KFFS2A2GDG66J7XD/"},{"type":"ADVISORY","url":"https://lists.debian.org/debian-lts-announce/2021/11/msg00007.html"},{"type":"FIX","url":"https://ckeditor.com/blog/ckeditor-4.16.1-with-accessibility-enhancements/#improvements-for-comments-in-html-parser"},{"type":"FIX","url":"https://www.drupal.org/sa-core-2021-003"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-07-08T06:00:39.834447918Z"}}