CVE-2024-43335 in Responsive Blocks Plugin
Summary
by MITRE • 08/18/2024
Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerability in CyberChimps Responsive Blocks – WordPress Gutenberg Blocks allows Stored XSS.This issue affects Responsive Blocks – WordPress Gutenberg Blocks: from n/a through 1.8.8.
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Analysis
by VulDB Data Team • 03/14/2025
This vulnerability represents a critical cross-site scripting flaw in the CyberChimps Responsive Blocks WordPress plugin that enables stored XSS attacks. The issue stems from improper input sanitization during web page generation processes, specifically within the Gutenberg block rendering functionality. When users create or edit content using the responsive blocks, malicious input can be injected and subsequently stored in the database, making it persistent across user sessions. The vulnerability affects versions prior to 1.8.8, indicating that the plugin developers identified and addressed this security gap in their update cycle. This type of vulnerability falls under CWE-79 which specifically addresses cross-site scripting in web applications. The flaw allows attackers to execute malicious scripts in the context of a victim's browser, potentially leading to session hijacking, data theft, or unauthorized actions performed on behalf of the user.
The operational impact of this stored XSS vulnerability extends beyond simple script execution, as it can be leveraged to compromise user sessions and escalate privileges within the WordPress environment. Attackers can inject malicious payloads through the plugin's input fields, which then get rendered when other users view the affected pages. This creates a persistent threat vector that can affect multiple users over time, making the vulnerability particularly dangerous for sites with active user communities or administrative interfaces. The attack surface is amplified when considering that WordPress sites often contain sensitive user data, administrative credentials, and business-critical information. This vulnerability aligns with ATT&CK technique T1531 which involves the use of credentials to gain access to systems, as successful XSS exploitation can lead to credential theft and session manipulation.
The remediation approach requires immediate patching of the affected plugin to version 1.8.8 or later, which should include proper input validation and output encoding mechanisms. Organizations should implement comprehensive input sanitization routines that filter and escape all user-provided content before storage and rendering. Additionally, security headers such as Content Security Policy should be implemented to provide additional protection against XSS attacks. Regular security audits and penetration testing of WordPress installations are essential to identify similar vulnerabilities in other plugins or themes. The vulnerability demonstrates the critical importance of input validation in web applications, particularly in content management systems where user-generated content is prevalent. Security professionals should also consider implementing web application firewalls and monitoring for suspicious input patterns to detect potential exploitation attempts before they can cause damage.