CVE-2026-24528 in Nova Blocks Plugin
Summary
by MITRE • 01/23/2026
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in pixelgrade Nova Blocks nova-blocks allows DOM-Based XSS.This issue affects Nova Blocks: from n/a through <= 2.1.9.
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Analysis
by VulDB Data Team • 01/23/2026
This vulnerability represents a critical cross-site scripting weakness in the pixelgrade Nova Blocks plugin that specifically impacts the DOM-based execution context. The flaw occurs during web page generation when user input is improperly handled, creating an environment where malicious scripts can be injected and executed within the browser context of legitimate users. The vulnerability is classified as a DOM-based XSS attack because the malicious payload is executed directly within the Document Object Model rather than being sent to a server-side processing endpoint.
The technical implementation of this vulnerability stems from insufficient input validation and sanitization mechanisms within the Nova Blocks plugin's web page generation process. When users interact with blocks that accept dynamic content or parameters, the plugin fails to properly neutralize potentially malicious input before incorporating it into the generated HTML structure. This allows attackers to craft specially formatted input that, when processed by the plugin, results in script execution within the victim's browser session. The vulnerability affects all versions of Nova Blocks up to and including version 2.1.9, indicating a persistent flaw that has not been adequately addressed in the plugin's codebase.
The operational impact of this vulnerability extends beyond simple script execution, as it can enable attackers to perform a wide range of malicious activities within the context of authenticated user sessions. An attacker could potentially steal session cookies, redirect users to malicious websites, modify page content, or even perform actions on behalf of the victim if they have sufficient privileges. The DOM-based nature of the attack means that the malicious script executes in the victim's browser without requiring server-side processing, making detection and prevention more challenging. This vulnerability particularly affects WordPress environments where Nova Blocks is installed, creating a vector for attackers to compromise user sessions and potentially gain unauthorized access to administrative functions.
Mitigation strategies should focus on immediate input validation and sanitization improvements within the plugin's codebase. The recommended approach involves implementing comprehensive content security policies that restrict script execution within the plugin's output, using proper escaping mechanisms for all dynamic content, and ensuring that user-supplied input undergoes strict validation before being incorporated into generated web pages. Organizations should also consider implementing web application firewalls that can detect and block suspicious script injection attempts, while monitoring for unusual patterns in user interactions with the affected plugin. The vulnerability aligns with CWE-79 which specifically addresses cross-site scripting flaws, and represents a clear violation of ATT&CK technique T1566.001 which covers social engineering through malicious content injection. Regular security audits and code reviews should be implemented to prevent similar issues in future plugin versions, with particular attention to the handling of dynamic content and user input in web page generation processes.