CVE-2025-40721
📋 TL;DR
A reflected Cross-site Scripting (XSS) vulnerability in Quiter Gateway allows attackers to execute malicious JavaScript in victims' browsers by crafting URLs with malicious payloads in the id_factura parameter. This affects organizations using Quiter Gateway versions before 4.7.0. Attackers can steal session cookies, redirect users, or perform actions on their behalf.
💻 Affected Systems
- Quiter Gateway
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Attacker steals administrator session cookies, gains full administrative access to the Quiter Gateway system, and potentially compromises sensitive financial data or performs unauthorized transactions.
Likely Case
Attacker steals user session cookies to impersonate legitimate users, accesses their financial data, or performs unauthorized actions within their permissions.
If Mitigated
With proper input validation and output encoding, the malicious script payloads are neutralized before reaching users' browsers, preventing execution.
🎯 Exploit Status
Reflected XSS vulnerabilities are commonly exploited with simple crafted URLs. No authentication required to trigger the vulnerability.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 4.7.0
Vendor Advisory: https://www.incibe.es/en/incibe-cert/notices/aviso/multiple-vulnerabilities-quiterweb-autoweb-quiter
Restart Required: Yes
Instructions:
1. Download Quiter Gateway version 4.7.0 from official vendor sources. 2. Backup current installation and data. 3. Stop the Quiter Gateway service. 4. Install/upgrade to version 4.7.0 following vendor documentation. 5. Restart the service and verify functionality.
🔧 Temporary Workarounds
Web Application Firewall (WAF) Rule
allConfigure WAF to block or sanitize requests containing suspicious patterns in the id_factura parameter.
WAF-specific configuration commands vary by product
Input Validation Filter
allImplement server-side input validation to restrict id_factura parameter to expected formats (e.g., numeric values only).
Implementation depends on application framework
🧯 If You Can't Patch
- Implement strict Content Security Policy (CSP) headers to prevent execution of inline scripts and restrict script sources.
- Deploy a reverse proxy with request filtering to sanitize or block malicious id_factura parameter values before reaching the application.
🔍 How to Verify
Check if Vulnerable:
Test by accessing the vulnerable endpoint with a harmless payload in the id_factura parameter (e.g., /client/FacturaE/listado_facturas_ficha.jsp?id_factura=<script>alert('test')</script>) and check if script executes.Check Version:
Check application documentation or interface for version information; typically found in admin panel or about section.Verify Fix Applied:
After patching, repeat the test with the same payload; the script should not execute, and the parameter should be properly sanitized or rejected.📡 Detection & Monitoring
Log Indicators:
- HTTP requests to /.../listado_facturas_ficha.jsp with suspicious id_factura parameter values containing script tags or JavaScript code
- Unusual user agent strings or referrers in requests to the vulnerable endpoint
Network Indicators:
- HTTP traffic containing malicious script payloads in URL parameters
- Requests with encoded or obfuscated JavaScript in id_factura parameter
SIEM Query:
source="web_server_logs" AND uri="*listado_facturas_ficha.jsp*" AND (param="*id_factura*<script>*" OR param="*id_factura*javascript:*")