CVE-2026-15084 in Drupal
Summary
by MITRE • 07/11/2026
Improper Neutralization of Input During Web Page Generation ("Cross-site Scripting") vulnerability in Drupal UI Patterns (SDC in Drupal UI) allows Stored XSS. This issue affects UI Patterns (SDC in Drupal UI) versions: from 2.0.0 to 2.0.17.
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Analysis
by VulDB Data Team • 07/11/2026
This vulnerability represents a critical cross-site scripting flaw within the Drupal UI Patterns module, specifically affecting versions between 2.0.0 and 2.0.17. The issue stems from improper input sanitization during web page generation processes, creating an environment where malicious actors can inject persistent script code into the application's user interface components. The vulnerability falls under CWE-79 which categorizes cross-site scripting as a fundamental web application security weakness involving the improper handling of untrusted data within web applications. This particular flaw enables attackers to execute arbitrary JavaScript code within the context of other users' browsers, potentially compromising user sessions and data integrity.
The technical implementation of this vulnerability occurs when the UI Patterns module processes user-provided input without adequate sanitization or encoding before rendering it in generated web pages. Attackers can exploit this weakness by submitting malicious payloads through forms or input fields that are subsequently stored within the application's database or configuration structures. These stored inputs are then rendered in subsequent page generations, executing the injected scripts when other users view the affected content. The vulnerability specifically impacts the SDC (Simple Drupal Components) functionality within the UI Patterns module, which provides reusable interface components for Drupal sites.
The operational impact of this stored XSS vulnerability extends beyond simple script execution, as it can enable attackers to perform session hijacking, steal sensitive user information, modify content, redirect users to malicious websites, or even escalate privileges within the application. Since the vulnerability affects the UI Patterns module's core functionality for generating user interface components, it can compromise multiple pages and sections of affected Drupal installations. The stored nature of this XSS attack means that once an attacker successfully injects malicious code, it persists until manually removed from the system, potentially affecting numerous users over extended periods.
Organizations affected by this vulnerability should immediately implement mitigations including upgrading to patched versions of the UI Patterns module where available, implementing proper input validation and output encoding mechanisms, and applying web application firewalls as additional protective layers. The ATT&CK framework categorizes this vulnerability under T1059.007 for Scripting and T1566 for Phishing, highlighting the potential for attackers to leverage such vulnerabilities for broader exploitation campaigns. Security teams should also conduct thorough audits of all user input handling mechanisms within their Drupal installations, establish regular security scanning protocols, and implement proper access controls to limit the impact of potential compromises. The vulnerability underscores the importance of maintaining up-to-date software components and implementing robust input sanitization practices as fundamental security measures against persistent web application threats.