CVE-2026-118549 in Drupal
Summary
by MITRE • 10/30/2026
Improper Neutralization of Input During Web Page Generation ("Cross-site Scripting") vulnerability in Drupal AI (Artificial Intelligence) allows Cross-Site Scripting (XSS). This issue affects AI (Artificial Intelligence) versions: from 0.0.0 to 1.4.11, from 1.5.0 to 1.5.2.
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Analysis
by VulDB Data Team • 10/30/2026
The Drupal AI module, which integrates artificial intelligence capabilities into the Drupal content management system, contains a critical security flaw classified as an Improper Neutralization of Input During Web Page Generation, commonly known as Cross-Site Scripting or XSS. This vulnerability affects versions ranging from 0.0.0 up to and including 1.4.11, as well as versions 1.5.0 through 1.5.2. The core issue stems from the module's failure to properly sanitize user-supplied input before it is rendered in web pages generated by the AI features. When a system processes data without adequate validation or encoding, malicious scripts can be injected into the output stream, which are then executed by the victim's browser under the context of the vulnerable site.
From a technical perspective, this vulnerability typically arises when user-controlled data, such as comments, form inputs, or configuration settings processed by the AI module, is inserted directly into HTML responses without applying appropriate encoding functions like htmlspecialchars() in PHP contexts. The attacker crafts a specific payload containing JavaScript code and submits it through an interface exposed by the Drupal AI module. Because the application trusts this input implicitly during the page generation phase, the browser interprets the injected script as legitimate content belonging to the site's domain. This allows the malicious code to run with the same privileges as any other script on the page, effectively bypassing standard security boundaries like the Same-Origin Policy that are designed to isolate web applications from each other.
The operational impact of this vulnerability is significant for organizations relying on Drupal AI for content generation or user interaction features. Successful exploitation enables an attacker to perform a range of malicious actions depending on the context and privileges of the targeted users. These actions include stealing session cookies, which can lead to account takeover if session fixation or hijacking techniques are employed. Attackers may also redirect victims to phishing sites designed to harvest credentials, deface web pages by altering DOM elements, or keylog user inputs within forms handled by the application. In environments where administrative privileges are involved, the impact escalates to full system compromise, allowing the attacker to execute arbitrary code on the server if combined with other vulnerabilities or through social engineering tactics that trick administrators into executing malicious scripts.
This flaw aligns closely with CWE-79, which defines Improper Neutralization of Input During Web Page Generation as a category where software does not properly neutralize user input before using it in web pages. Furthermore, the exploitation technique maps to MITRE ATT&CK techniques such as T1059 Command and Scripting Interpreter for executing JavaScript payloads and potentially T1204 User Execution if social engineering is used to trigger the payload. The vulnerability highlights a common oversight in modern AI-integrated applications where complex data processing pipelines may inadvertently bypass standard input validation layers, assuming that internal logic handles safety rather than explicit sanitization at the output boundary.
To mitigate this risk, organizations must immediately upgrade the Drupal AI module to version 1.5.3 or later, which addresses these specific encoding failures. For sites unable to update instantly due to compatibility constraints, temporary mitigations should include implementing a Web Application Firewall that can detect and block common XSS payloads in HTTP requests targeting the affected endpoints. Additionally, developers should review any custom code interacting with the AI module to ensure that all user inputs are strictly validated against expected formats and encoded appropriately before being rendered in HTML contexts. Enabling Content Security Policy headers on the web server can also provide a layer of defense by restricting the sources from which scripts can be loaded or executed, thereby limiting the impact even if an injection attempt succeeds. Regular security audits and penetration testing focused on input validation across all AI-driven features are recommended to prevent similar oversights in future updates.