CVE-2025-46502: LSD Custom Taxonomy CSRF Vulnerability

CVE-2025-46502 Overview

CVE-2025-46502 is a Cross-Site Scripting (XSS) vulnerability combined with Cross-Site Request Forgery (CSRF) in the LSD Custom taxonomy and category meta WordPress plugin developed by Bas Matthee. The vulnerability arises from improper neutralization of input during web page generation, allowing attackers to execute arbitrary scripts in the context of authenticated users' browsers through crafted CSRF attacks.

Critical Impact

Attackers can chain CSRF with XSS to execute malicious scripts in authenticated user sessions, potentially leading to session hijacking, data theft, or administrative account compromise on WordPress sites using this plugin.

Affected Products

• LSD Custom taxonomy and category meta plugin version 1.3.2 and earlier
• WordPress installations using the custom-taxonomy-category-and-term-fields plugin
• All versions from initial release through version 1.3.2

Discovery Timeline

• 2025-04-24 - CVE CVE-2025-46502 published to NVD
• 2026-04-23 - Last updated in NVD database

Technical Details for CVE-2025-46502

Vulnerability Analysis

This vulnerability is classified under CWE-79 (Improper Neutralization of Input During Web Page Generation). The plugin fails to properly validate and sanitize user-supplied input before rendering it in web pages, combined with missing CSRF token validation on sensitive operations. This creates a chained attack scenario where malicious actors can craft requests that both bypass CSRF protections and inject malicious scripts into the application.

The vulnerability requires user interaction (a victim must click a malicious link or visit an attacker-controlled page), but once triggered, the attack can affect the broader security context of the WordPress installation. The scope is changed (S:C), meaning the vulnerable component impacts resources beyond its security scope, affecting confidentiality, integrity, and availability at low levels.

Root Cause

The root cause stems from two combined security failures in the plugin:

1. Missing CSRF Protection: The plugin does not implement proper nonce verification on form submissions or AJAX requests that modify taxonomy and category meta data
2. Insufficient Input Sanitization: User-controlled input is reflected in the page output without proper encoding or escaping, allowing script injection

These deficiencies in the custom-taxonomy-category-and-term-fields plugin create an exploitable condition where attackers can forge requests on behalf of authenticated administrators and inject persistent or reflected XSS payloads.

Attack Vector

The attack is network-based and requires user interaction. An attacker would typically:

1. Craft a malicious webpage or email containing a forged request targeting the vulnerable plugin endpoint
2. Trick an authenticated WordPress administrator into visiting the malicious page
3. The forged request executes in the context of the victim's session, injecting malicious JavaScript
4. The XSS payload executes when the injected content is rendered, potentially stealing session cookies or performing unauthorized actions

The vulnerability can be exploited without authentication on the attacker's part, though an authenticated victim (typically with administrative privileges) is required for successful exploitation.

For detailed technical information about this vulnerability, refer to the Patchstack Vulnerability Report.

Detection Methods for CVE-2025-46502

Indicators of Compromise

• Unexpected modifications to taxonomy or category meta fields containing script tags or event handlers
• Unusual HTTP POST requests to plugin endpoints from external referrers
• JavaScript payloads in database entries for custom taxonomy fields
• Browser console errors indicating blocked inline scripts (if CSP is enabled)

Detection Strategies

• Monitor WordPress database tables associated with taxonomy meta for suspicious content patterns such as <script>, onerror=, or javascript: strings
• Implement Web Application Firewall (WAF) rules to detect CSRF attack patterns targeting the plugin's form endpoints
• Review server access logs for POST requests to plugin endpoints with external or suspicious Referer headers
• Deploy SentinelOne Singularity to detect and alert on anomalous script execution patterns within the WordPress environment

Monitoring Recommendations

• Enable WordPress audit logging to track changes to taxonomy and category metadata
• Configure Content Security Policy (CSP) headers to restrict inline script execution and report violations
• Implement real-time file integrity monitoring on WordPress plugin directories
• Set up alerting for administrative actions performed immediately after external site visits

How to Mitigate CVE-2025-46502

Immediate Actions Required

• Deactivate and remove the LSD Custom taxonomy and category meta plugin (custom-taxonomy-category-and-term-fields) version 1.3.2 or earlier immediately
• Audit existing taxonomy and category meta entries for injected malicious content
• Review administrator account activity logs for signs of compromise
• Implement a Web Application Firewall with CSRF and XSS protection rules

Patch Information

As of the vulnerability disclosure, all versions through 1.3.2 are affected. Website administrators should check for updated versions from the plugin author or consider using alternative plugins with better security practices. Monitor the Patchstack Vulnerability Report for patch availability announcements.

Workarounds

• Remove or deactivate the vulnerable plugin until a patched version is available
• Implement strict Content Security Policy headers to mitigate XSS impact: Content-Security-Policy: script-src 'self';
• Add custom CSRF protection at the server or WAF level for the plugin's endpoints
• Restrict WordPress admin panel access to trusted IP addresses only

# WordPress .htaccess CSP header configuration
<IfModule mod_headers.c>
    Header set Content-Security-Policy "script-src 'self'; frame-ancestors 'self';"
    Header set X-Content-Type-Options "nosniff"
    Header set X-XSS-Protection "1; mode=block"
</IfModule>