CVE-2025-53342 in Modernize Plugin
Summary
by MITRE • 08/14/2025
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in GoodLayers Modernize allows Stored XSS. This issue affects Modernize: from n/a through 3.4.0.
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Analysis
by VulDB Data Team • 08/14/2025
This vulnerability represents a critical cross-site scripting flaw in the GoodLayers Modernize WordPress theme that enables stored XSS attacks. The weakness occurs during web page generation when user input is not properly sanitized or escaped before being rendered in HTML output. Attackers can inject malicious scripts that persist in the application's database and execute whenever other users view affected pages. The vulnerability affects all versions of Modernize up to and including version 3.4.0, indicating a widespread exposure across multiple releases. This type of vulnerability falls under CWE-79 which specifically addresses cross-site scripting flaws where input data is improperly handled during web page construction. The stored nature of this XSS means that malicious payloads remain active in the system long after initial injection, making it particularly dangerous for persistent attacks.
The technical exploitation of this vulnerability occurs when user-submitted content or parameters are directly incorporated into HTML output without proper encoding or validation. This allows attackers to inject malicious JavaScript code that executes in the context of other users' browsers. The vulnerability's impact extends beyond simple script execution as it can enable session hijacking, credential theft, and redirection to malicious sites. Attackers can leverage this weakness to compromise user accounts, deface websites, or establish persistent backdoors within the affected environment. The vulnerability's presence in the theme's core functionality suggests that it likely affects multiple page types and user interactions within the WordPress ecosystem.
From an operational perspective, this vulnerability creates significant risk for organizations using the Modernize theme as it allows attackers to gain unauthorized access to user sessions and potentially escalate privileges. The stored XSS nature means that even users who do not actively interact with the compromised pages can be affected when their browsers render the malicious content. This makes the attack surface much broader than typical reflected XSS scenarios. Security teams must consider the potential for data exfiltration, user account compromise, and reputational damage when assessing the impact of this vulnerability. The issue directly aligns with ATT&CK technique T1531 which involves establishing persistence through malicious scripts and T1566 which covers social engineering via malicious content delivery.
Organizations should implement immediate mitigation strategies including updating to the latest version of the Modernize theme where the vulnerability has been patched. Input validation and output encoding should be strengthened throughout the application to prevent similar issues in the future. Regular security audits of third-party themes and plugins are essential to identify potential XSS vulnerabilities. Browser security features such as Content Security Policy headers can provide additional protection layers. The vulnerability demonstrates the critical importance of proper input sanitization and output encoding practices as recommended by OWASP and other security frameworks. Organizations should also consider implementing web application firewalls and monitoring for suspicious script injection patterns to detect and prevent exploitation attempts.