Name: CVE-2021-33829: Improper Neutralization of Input During Web Page Generation
Creator: Rapid7
Published: 2021-06-09T00:00:00.000Z
License: https://www.rapid7.com/legal/website-terms-of-use/
Keywords: CVE, CVE-2021-33829, CWE-79, CVSS 6.1, EPSS 0.03189

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.

CVSS Details

CVSS 3.1 Base Score: 6.1
CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N)

Covered by Rapid7

Product	Vendor Advisory	Solution File	Added	Published
Arch Linux	—	Upgrade to the latest version of Arch Linux	Jul 11, 2025	Jun 9, 2021
Debian	—	Upgrade ckeditor	Nov 29, 2021	Jun 9, 2021
Drupal	—	Upgrade to drupal version 8.9.1Upgrade to drupal version 9.0.1Upgrade to drupal version 9.1.9	Mar 23, 2022	Jun 9, 2021
Ubuntu	—	Upgrade ckeditor	Mar 23, 2022	Jun 9, 2021

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CVSS Details

Covered by Rapid7

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