CVE-2025-31901: Digihood HTML Sitemap XSS Vulnerability

CVE-2025-31901 Overview

A Reflected Cross-Site Scripting (XSS) vulnerability has been identified in the Digihood HTML Sitemap WordPress plugin (wedesin-html-sitemap). This vulnerability stems from improper neutralization of user input during web page generation, allowing attackers to inject malicious scripts that execute in the context of a victim's browser session.

Reflected XSS vulnerabilities occur when user-supplied data is immediately returned by a web application without proper sanitization or encoding. In this case, the Digihood HTML Sitemap plugin fails to adequately sanitize input parameters, enabling attackers to craft malicious URLs that, when clicked by authenticated users, execute arbitrary JavaScript code within their browser.

Critical Impact

Attackers can exploit this vulnerability to steal session cookies, hijack user accounts, perform unauthorized actions on behalf of victims, or redirect users to malicious websites. WordPress administrators clicking malicious links could have their admin sessions compromised.

Affected Products

• Digihood HTML Sitemap (wedesin-html-sitemap) version 3.1.1 and earlier
• All WordPress installations running vulnerable versions of the plugin

Discovery Timeline

• 2025-04-03 - CVE-2025-31901 published to NVD
• 2026-04-15 - Last updated in NVD database

Technical Details for CVE-2025-31901

Vulnerability Analysis

This vulnerability is classified under CWE-79 (Improper Neutralization of Input During Web Page Generation), commonly known as Cross-Site Scripting. The Digihood HTML Sitemap plugin contains code paths that reflect user-controlled input directly into web page output without proper encoding or sanitization.

Reflected XSS attacks require social engineering to be successful, as the attacker must convince a victim to click on a specially crafted URL containing the malicious payload. Once clicked, the malicious script executes within the victim's authenticated browser session, potentially allowing the attacker to perform actions as that user.

The vulnerability affects all versions of the plugin from its initial release through version 3.1.1. WordPress sites using this plugin for generating HTML sitemaps are at risk if users interact with attacker-controlled links.

Root Cause

The root cause of this vulnerability lies in insufficient input validation and output encoding within the plugin's request handling logic. When processing URL parameters or form inputs, the plugin fails to apply proper sanitization functions such as esc_html(), esc_attr(), or wp_kses() before rendering user-supplied data in HTML output.

WordPress provides built-in sanitization and escaping functions specifically designed to prevent XSS vulnerabilities. The failure to implement these security controls allows raw user input to be reflected in the page response, creating the XSS condition.

Attack Vector

The attack vector for this Reflected XSS vulnerability involves crafting a malicious URL containing JavaScript payload in a vulnerable parameter. The attacker then distributes this URL through phishing emails, social media, or other communication channels. When a victim clicks the link while authenticated to the WordPress site, the malicious script executes in their browser context.

Potential attack scenarios include:

• Session hijacking through cookie theft
• Credential harvesting via fake login forms
• Administrative action execution (creating rogue admin accounts, modifying content)
• Malware distribution through redirect chains
• Defacement of the WordPress site for the victim's session

The vulnerability manifests when unsanitized input parameters are reflected in the plugin's HTML output. For detailed technical information about the exploitation mechanism, refer to the Patchstack Plugin Vulnerability Advisory.

Detection Methods for CVE-2025-31901

Indicators of Compromise

• Suspicious URL parameters containing JavaScript code or encoded script payloads in requests to WordPress pages using the sitemap plugin
• Unusual redirect chains or external resource loading from untrusted domains
• Web server access logs showing requests with XSS-related patterns such as <script>, javascript:, or encoded equivalents
• Reports from users of unexpected behavior when clicking links related to the sitemap functionality

Detection Strategies

• Deploy Web Application Firewall (WAF) rules to detect and block common XSS payload patterns in URL parameters
• Implement Content Security Policy (CSP) headers to restrict inline script execution and report violations
• Monitor web server access logs for requests containing suspicious encoded characters or script tags
• Use browser-based XSS auditors and security extensions for real-time detection

Monitoring Recommendations

• Enable detailed logging for the WordPress installation and review logs for anomalous request patterns
• Configure security plugins such as Wordfence or Sucuri to alert on detected XSS attempts
• Implement real-time alerting for CSP violation reports from browsers
• Regularly scan the WordPress installation with vulnerability scanners to identify unpatched plugins

How to Mitigate CVE-2025-31901

Immediate Actions Required

• Update the Digihood HTML Sitemap plugin to the latest available version that addresses this vulnerability
• If no patch is available, consider temporarily deactivating the wedesin-html-sitemap plugin until a fix is released
• Implement Web Application Firewall rules to filter malicious XSS payloads
• Review web server logs for any evidence of exploitation attempts
• Educate WordPress administrators about the risks of clicking untrusted links

Patch Information

Consult the Patchstack Plugin Vulnerability Advisory for the latest patch status and remediation guidance. Plugin updates can be applied through the WordPress admin dashboard under Plugins > Installed Plugins, or by downloading the latest version from the WordPress plugin repository.

Workarounds

• Temporarily deactivate the Digihood HTML Sitemap plugin if immediate patching is not possible
• Implement strict Content Security Policy headers to prevent inline script execution
• Deploy ModSecurity or similar WAF with OWASP Core Rule Set to block XSS attempts
• Restrict access to WordPress admin areas using IP allowlisting or VPN requirements
• Consider using an alternative HTML sitemap plugin that has been audited for security

# Example: Add Content Security Policy header in .htaccess for Apache
# This helps mitigate XSS by restricting inline script execution
Header set Content-Security-Policy "default-src 'self'; script-src 'self'; style-src 'self' 'unsafe-inline';"