CVE-2025-48884 Overview
CVE-2025-48884 is a Cross-Site Scripting (XSS) vulnerability affecting Galette, a membership management web application used by non-profit organizations. The flaw resides in the Document Type feature and allows attackers to inject malicious script content that executes in the context of victim browsers. Galette versions 1.1.5.2 and below are affected, and the issue is fixed in version 1.2.0. The vulnerability is classified under CWE-79 (Improper Neutralization of Input During Web Page Generation) and CWE-80 (Improper Neutralization of Script-Related HTML Tags).
Critical Impact
Attackers can execute arbitrary JavaScript in the browsers of authenticated Galette users, enabling session theft, unauthorized actions, and manipulation of membership data.
Affected Products
- Galette versions up to and including 1.1.5.2
- Galette 1.2.0 alpha pre-release builds
- Galette Document Type functionality across all deployments below 1.2.0
Discovery Timeline
- 2025-11-04 - CVE-2025-48884 published to NVD
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2025-48884
Vulnerability Analysis
The vulnerability exists in Galette's Document Type feature, which fails to properly neutralize user-supplied input before rendering it in HTML output. When an attacker submits crafted content containing script tags or HTML event handlers, the application stores or reflects that input without adequate sanitization. Any user viewing the affected page then triggers script execution in their browser session.
Exploitation requires user interaction, as indicated by the CVSS vector component UI:P. An attacker must convince a target to visit a page containing the injected payload or interact with a malicious Document Type entry. The confidentiality and integrity impacts are limited to browser-scoped resources such as session cookies, form data, and rendered content.
Root Cause
The root cause is improper output encoding of Document Type fields in the Galette web interface. The application accepts input intended for document metadata but does not apply context-aware HTML escaping when rendering that data. This maps to CWE-80, which specifically covers failure to neutralize script-related HTML tags in a webpage.
Attack Vector
The attack is delivered over the network through Galette's web interface. An attacker with the ability to create or modify Document Type entries injects a payload containing JavaScript. When an administrator or member views the affected view, the browser parses and executes the injected script. Refer to the Galette Security Advisory GHSA-3rc3-rc5x-vmr4 for technical details.
Detection Methods for CVE-2025-48884
Indicators of Compromise
- Unexpected <script> tags, javascript: URIs, or HTML event handlers (onerror, onload) stored in Document Type records
- Outbound HTTP requests from user browsers to unfamiliar domains shortly after loading Galette pages
- Anomalous session activity following Document Type views, such as unauthorized account modifications
Detection Strategies
- Review the Galette database for Document Type entries containing HTML or JavaScript markup
- Inspect web server access logs for POST requests to Document Type endpoints with suspicious payloads
- Deploy a Content Security Policy (CSP) in report-only mode to surface script execution from untrusted sources
Monitoring Recommendations
- Monitor authentication and privileged action logs for activity that follows Document Type page views
- Alert on Galette application errors related to template rendering or unexpected characters in stored fields
- Track version metadata across Galette installations to identify hosts running vulnerable releases
How to Mitigate CVE-2025-48884
Immediate Actions Required
- Upgrade Galette to version 1.2.0 or later, which contains the vendor-supplied fix
- Audit existing Document Type records and remove any entries containing HTML or script content
- Restrict Document Type editing permissions to trusted administrative accounts until patched
Patch Information
The vendor released a fix in Galette 1.2.0. Administrators should follow the upgrade guidance in the Galette Security Advisory GHSA-3rc3-rc5x-vmr4. Verify the installed version after upgrade and confirm that Document Type input is properly escaped on render.
Workarounds
- Apply a strict Content Security Policy that disallows inline scripts on Galette pages
- Place the application behind a web application firewall configured to block reflected and stored XSS payloads
- Limit access to Document Type creation and editing to a minimal set of trusted users until the upgrade is completed
# Example Content-Security-Policy header for Galette (Apache)
Header set Content-Security-Policy "default-src 'self'; script-src 'self'; object-src 'none'; base-uri 'self'; frame-ancestors 'self'"
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
