CVE-2025-58852: MSTW League Manager CSRF Vulnerability

CVE-2025-58852 Overview

CVE-2025-58852 is a Cross-Site Request Forgery (CSRF) vulnerability in the MSTW League Manager WordPress plugin developed by Mark O'Donnell. This vulnerability enables attackers to chain CSRF with Stored Cross-Site Scripting (XSS), allowing malicious actors to inject persistent scripts into the application when authenticated administrators perform state-changing actions without proper validation.

The vulnerability exists because the plugin fails to implement proper CSRF token validation on sensitive form submissions, which can be exploited to inject malicious JavaScript payloads that persist in the database and execute whenever users access affected pages.

Critical Impact

Attackers can leverage this CSRF-to-Stored-XSS chain to hijack administrator sessions, modify plugin settings, inject malicious content into WordPress sites, or redirect visitors to malicious domains.

Affected Products

• MSTW League Manager WordPress Plugin versions through 2.10
• WordPress installations with MSTW League Manager plugin enabled

Discovery Timeline

• 2025-09-05 - CVE-2025-58852 published to NVD
• 2026-04-15 - Last updated in NVD database

Technical Details for CVE-2025-58852

Vulnerability Analysis

This vulnerability combines two distinct attack classes: Cross-Site Request Forgery (CWE-352) and Stored Cross-Site Scripting. The MSTW League Manager plugin fails to validate the origin of form submissions, allowing attackers to craft malicious requests that execute in the context of authenticated administrators.

When an administrator visits an attacker-controlled page while logged into WordPress, the malicious page can automatically submit forms to the vulnerable plugin endpoints. Because the plugin does not verify CSRF tokens (nonces in WordPress terminology), these forged requests are processed as legitimate. The injected content is then stored in the database and rendered without proper sanitization, resulting in persistent XSS.

The attack surface extends to any functionality within the League Manager plugin that accepts user input and stores it for later display, including team names, league configurations, and other management settings.

Root Cause

The root cause of this vulnerability is the absence of WordPress nonce verification on form submission handlers within the MSTW League Manager plugin. WordPress provides built-in CSRF protection through its nonce system via functions like wp_nonce_field() and wp_verify_nonce(), but the plugin fails to implement these security controls on state-changing operations.

Additionally, the plugin does not properly sanitize or escape user-supplied input before storing it in the database or rendering it in the browser, enabling the Stored XSS component of this attack chain.

Attack Vector

The attack requires social engineering to trick an authenticated WordPress administrator into visiting a malicious webpage. The attacker crafts an HTML page containing a hidden form that automatically submits to the vulnerable plugin endpoint when loaded. This form includes malicious JavaScript payloads in fields that are later rendered without proper escaping.

The attack flow proceeds as follows: the administrator visits the attacker's page, which triggers an automatic form submission to the WordPress admin panel. The plugin processes this request without CSRF validation, stores the malicious payload, and subsequently executes the injected script whenever the affected content is displayed to any user.

For technical details regarding this vulnerability, refer to the Patchstack vulnerability database entry.

Detection Methods for CVE-2025-58852

Indicators of Compromise

• Unexpected or unauthorized changes to league manager settings, team names, or configuration options
• JavaScript code appearing in database fields associated with the MSTW League Manager plugin
• Administrative actions logged without corresponding legitimate user activity
• Suspicious <script> tags or event handlers (e.g., onload, onerror) in plugin-related database entries

Detection Strategies

• Monitor WordPress admin action logs for unusual modifications to MSTW League Manager settings
• Implement Content Security Policy (CSP) headers to detect and block inline script execution attempts
• Deploy web application firewall (WAF) rules to identify CSRF attack patterns targeting WordPress plugins
• Perform regular database audits scanning for JavaScript or HTML injection patterns in plugin tables

Monitoring Recommendations

• Enable WordPress audit logging to track all administrative changes to plugin configurations
• Configure alerts for bulk or rapid modifications to league manager data
• Monitor HTTP referrer headers for administrative POST requests originating from external domains
• Review server access logs for unusual patterns of requests to WordPress admin endpoints

How to Mitigate CVE-2025-58852

Immediate Actions Required

• Deactivate the MSTW League Manager plugin until a patched version is available
• Audit existing league manager database entries for signs of XSS payload injection
• Review WordPress admin access logs for suspicious activity
• Implement additional WAF rules to block CSRF attempts targeting the plugin

Patch Information

No official patch information is currently available. Users should monitor the plugin's official WordPress.org page and the Patchstack vulnerability database for updates regarding a security fix.

Workarounds

• Disable or remove the MSTW League Manager plugin until a security update is released
• Implement Content Security Policy headers to mitigate the impact of potential XSS execution
• Restrict WordPress admin panel access to trusted IP addresses only
• Use a WordPress security plugin with CSRF protection capabilities to add an additional layer of defense
• Educate administrators about the risks of visiting untrusted websites while logged into WordPress

# Add CSP headers to WordPress via .htaccess (Apache)
<IfModule mod_headers.c>
    Header set Content-Security-Policy "default-src 'self'; script-src 'self'; style-src 'self' 'unsafe-inline';"
</IfModule>