CVE-2025-13981: Drupal AI Module XSS Vulnerability

CVE-2025-13981 Overview

CVE-2025-13981 is a Cross-Site Scripting (XSS) vulnerability affecting the Drupal AI (Artificial Intelligence) module. The vulnerability stems from improper neutralization of input during web page generation, allowing attackers to inject malicious scripts that execute in the context of authenticated user sessions. This flaw enables adversaries to potentially steal session tokens, perform actions on behalf of users, or redirect users to malicious sites.

Critical Impact

Authenticated attackers can exploit this XSS vulnerability to inject malicious scripts, potentially compromising user sessions and sensitive data within Drupal installations using the AI module.

Affected Products

• Drupal AI (Artificial Intelligence) module versions 0.0.0 to 1.0.6
• Drupal AI (Artificial Intelligence) module versions 1.1.0 to 1.1.6
• Drupal AI (Artificial Intelligence) module versions 1.2.0 to 1.2.3

Discovery Timeline

• 2026-01-28 - CVE-2025-13981 published to NVD
• 2026-01-29 - Last updated in NVD database

Technical Details for CVE-2025-13981

Vulnerability Analysis

This Cross-Site Scripting vulnerability exists due to insufficient input sanitization within the Drupal AI module. The module fails to properly neutralize user-supplied input before incorporating it into dynamically generated web pages. When malicious input containing JavaScript code is processed by the vulnerable component, the script executes within the browser context of users viewing the affected page.

The attack requires network access and authenticated access with low privileges. User interaction is required for successful exploitation, as a victim must interact with the malicious content. Successful exploitation can impact the confidentiality and integrity of data across the trust boundary, though availability is not affected.

Root Cause

The root cause of CVE-2025-13981 is classified as CWE-79 (Improper Neutralization of Input During Web Page Generation). The Drupal AI module does not adequately sanitize or encode user-controlled input before rendering it in HTML output. This allows specially crafted input containing script tags or event handlers to be interpreted as executable code rather than being treated as plain text data.

Attack Vector

The attack is network-based and requires an authenticated user with low privileges to inject malicious content. The exploitation complexity is high, and successful attacks require victim interaction—typically through clicking a malicious link or viewing a page containing the injected payload. Due to the scope change characteristic, the vulnerability can impact resources beyond the vulnerable component's security scope.

An attacker could craft a malicious payload containing JavaScript code and submit it through the AI module's input fields. When another user views the page containing this unsanitized input, the malicious script executes in their browser, potentially allowing the attacker to steal session cookies, capture keystrokes, or perform actions as the victim user.

Detection Methods for CVE-2025-13981

Indicators of Compromise

• Unusual JavaScript code appearing in AI module input fields or stored content
• Unexpected outbound requests to external domains from user browsers when interacting with AI module pages
• Session anomalies or unauthorized actions following user interaction with AI module content
• Web application firewall logs showing XSS payload patterns targeting AI module endpoints

Detection Strategies

• Implement web application firewall (WAF) rules to detect and block common XSS payload patterns
• Enable Content Security Policy (CSP) headers to restrict script execution and report violations
• Monitor server-side logs for suspicious input patterns containing script tags, event handlers, or encoded JavaScript
• Deploy browser-based XSS detection tools to identify malicious script injection attempts

Monitoring Recommendations

• Configure logging for all input submitted to AI module endpoints
• Enable CSP report-uri or report-to directives to capture policy violations indicating potential XSS attempts
• Monitor user session behavior for anomalies following interaction with AI module features
• Regularly audit AI module content for suspicious script injections or encoded payloads

How to Mitigate CVE-2025-13981

Immediate Actions Required

• Update Drupal AI module to version 1.0.7 or later for installations running versions 0.0.0 through 1.0.6
• Update Drupal AI module to version 1.1.7 or later for installations running versions 1.1.0 through 1.1.6
• Update Drupal AI module to version 1.2.4 or later for installations running versions 1.2.0 through 1.2.3
• Review AI module content for any previously injected malicious scripts

Patch Information

Security patches addressing this vulnerability are available through the official Drupal security advisory. The patched versions are 1.0.7, 1.1.7, and 1.2.4 for their respective version branches. Organizations should apply the appropriate patch based on their current AI module version. For complete details, refer to the Drupal Security Advisory SA-CONTRIB-2025-119.

Workarounds

• Implement strict Content Security Policy headers to prevent inline script execution
• Deploy a web application firewall with XSS protection rules enabled
• Restrict access to the AI module to trusted users only until patching is complete
• Enable Drupal's built-in input sanitization features for all content types used with the AI module

# Example: Add Content Security Policy header in Apache configuration
# Add to .htaccess or virtual host configuration
Header set Content-Security-Policy "default-src 'self'; script-src 'self'; style-src 'self' 'unsafe-inline';"