CVE-2021-33829

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.

• CWE-79

• https://ckeditor.com/blog/ckeditor-4.16.1-with-accessibility-enhancements/#improvements-for-comments-in-html-parserPatch, Release Notes, Vendor Advisory
• https://lists.debian.org/debian-lts-announce/2021/11/msg00007.htmlMailing List, Third Party Advisory
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NYA354LJP47KCVJMTUO77ZCX3ZK42G3T/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/UVOYN2WKDPLKCNILIGEZM236ABQASLGW/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WAGNWHFIQAVCP537KFFS2A2GDG66J7XD/
• https://www.drupal.org/sa-core-2021-003Patch, Third Party Advisory
• https://ckeditor.com/blog/ckeditor-4.16.1-with-accessibility-enhancements/#improvements-for-comments-in-html-parserPatch, Release Notes, Vendor Advisory
• https://lists.debian.org/debian-lts-announce/2021/11/msg00007.htmlMailing List, Third Party Advisory
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NYA354LJP47KCVJMTUO77ZCX3ZK42G3T/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/UVOYN2WKDPLKCNILIGEZM236ABQASLGW/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WAGNWHFIQAVCP537KFFS2A2GDG66J7XD/
• https://www.drupal.org/sa-core-2021-003Patch, Third Party Advisory

Published

Jun 9, 2021

Last Modified

Jun 17, 2026

Status

Modified

• How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
• Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
• PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
• AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.

• CVE-2021-33820An issue was discovered in UniFi Protect G3 FLEX Camera Vers…7.5
• CVE-2021-33822An issue was discovered on 4GEE ROUTER HH70VB Version HH70_E…7.5
• CVE-2021-33823An issue was discovered on MOXA Mgate MB3180 Version 2.1 Bui…7.5
• CVE-2021-33824An issue was discovered on MOXA Mgate MB3180 Version 2.1 Bui…7.5
• CVE-2021-33827The files_antivirus component before 1.0.0 for ownCloud allo…7.2
• CVE-2021-33828The files_antivirus component before 1.0.0 for ownCloud mish…8.8
• CVE-2021-33831api/account/register in the TH Wildau COVID-19 Contact Traci…6.5
• CVE-2021-33833ConnMan (aka Connection Manager) 1.30 through 1.39 has a sta…9.8
• CVE-2021-33834An issue was discovered in iscflashx64.sys 3.9.3.0 in Insyde…7.1
• CVE-2021-33838Luca through 1.7.4 on Android allows remote attackers to obt…7.5
• CVE-2021-33839Luca through 1.7.4 on Android allows remote attackers to obt…7.5
• CVE-2021-3384A vulnerability in Stormshield Network Security could allow …5.3