CVE-2022-24728 in CKEditor
Summary
by MITRE • 03/16/2022
CKEditor4 is an open source what-you-see-is-what-you-get HTML editor. A vulnerability has been discovered in the core HTML processing module and may affect all plugins used by CKEditor 4 prior to version 4.18.0. The vulnerability allows someone to inject malformed HTML bypassing content sanitization, which could result in executing JavaScript code. This problem has been patched in version 4.18.0. There are currently no known workarounds.
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Analysis
by VulDB Data Team • 03/18/2026
The vulnerability identified as CVE-2022-24728 represents a critical security flaw within CKEditor4's core HTML processing module that affects all plugins in versions prior to 4.18.0. This issue stems from inadequate content sanitization mechanisms that fail to properly validate and filter malformed HTML input, creating a pathway for malicious actors to inject dangerous code into the editor environment. The vulnerability specifically targets the HTML parsing and sanitization routines that are fundamental to CKEditor4's operation, making it particularly dangerous given the widespread adoption of this editor across numerous web applications and content management systems.
The technical exploitation of this vulnerability occurs through the injection of malformed HTML sequences that can bypass the editor's built-in content filtering mechanisms. When CKEditor4 processes such malformed input, the sanitization module fails to properly identify and neutralize potentially malicious HTML constructs, allowing JavaScript code execution within the context of the editor. This behavior aligns with CWE-79 which describes Cross-Site Scripting (XSS) vulnerabilities that occur when user-provided data is not properly validated or sanitized before being rendered in web applications. The flaw essentially creates a code injection vector that can be leveraged to execute arbitrary JavaScript within the victim's browser context, potentially leading to session hijacking, data theft, or further exploitation of the compromised system.
The operational impact of CVE-2022-24728 extends beyond simple code injection as it represents a fundamental breakdown in the editor's security architecture that affects all plugins and extensions within the CKEditor4 ecosystem. This vulnerability undermines the trust model that web applications rely upon when integrating rich text editors, as it allows attackers to bypass the security controls that should prevent malicious content from being processed. The implications are particularly severe for web applications that use CKEditor4 for user-generated content, as attackers can craft malicious HTML that appears legitimate to end users while simultaneously executing harmful scripts. This vulnerability directly maps to ATT&CK technique T1566.001 which covers the use of malicious HTML content to execute code in web browsers, making it a significant concern for organizations that deploy CKEditor4 in production environments.
Organizations utilizing CKEditor4 must prioritize immediate remediation through the upgrade to version 4.18.0 or later, as no effective workarounds exist for this vulnerability. The patch implemented in version 4.18.0 addresses the core sanitization flaws by strengthening the HTML parsing logic and implementing more robust validation mechanisms that properly identify and neutralize malformed HTML sequences. Security teams should conduct comprehensive audits of all web applications that incorporate CKEditor4 to identify potential exposure and ensure proper patch deployment across all affected systems. The vulnerability demonstrates the critical importance of maintaining up-to-date software components and implementing proper input validation as a defense-in-depth strategy against code injection attacks. Given the nature of this flaw, organizations should also consider implementing additional security controls such as content security policies and web application firewalls to provide layered protection against similar vulnerabilities that may exist in other components of their web applications.