CVE-2025-41053
📋 TL;DR
This vulnerability allows authenticated attackers to inject malicious scripts into appRain CMF through layout parameters, which execute when other users view affected pages. It affects organizations using appRain CMF version 4.0.5 for content management. The stored XSS can lead to session hijacking, data theft, or unauthorized actions.
💻 Affected Systems
- appRain CMF
📦 What is this software?
Apprain by Apprain
⚠️ Risk & Real-World Impact
Worst Case
Attackers could steal administrator credentials, compromise user accounts, deface websites, or redirect users to malicious sites, potentially leading to full system compromise.
Likely Case
Attackers with authenticated access inject malicious scripts that execute in victims' browsers, enabling session hijacking, data theft, or unauthorized content modifications.
If Mitigated
With proper input validation and output encoding, the vulnerability is prevented, though authenticated users still have legitimate access to the affected functionality.
🎯 Exploit Status
Exploitation requires authenticated access to the vulnerable endpoint. No public exploit code is currently available.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check vendor advisory for patched version
Vendor Advisory: https://www.incibe.es/en/incibe-cert/notices/aviso/multiple-vulnerabilities-apprain-cmf
Restart Required: No
Instructions:
1. Check the vendor advisory for patched version. 2. Update appRain CMF to the patched version. 3. Verify the fix by testing the vulnerable parameters.
🔧 Temporary Workarounds
Input Validation and Sanitization
allImplement server-side validation and sanitization for the 'data[Addon][layouts]' and 'data[Addon][layouts_except]' parameters to prevent XSS payloads.
🧯 If You Can't Patch
- Restrict access to the /apprain/developer/addons/update/commonresource endpoint to trusted administrators only.
- Implement a Web Application Firewall (WAF) with XSS protection rules to block malicious payloads.
🔍 How to Verify
Check if Vulnerable:
Test the /apprain/developer/addons/update/commonresource endpoint with XSS payloads in the 'data[Addon][layouts]' and 'data[Addon][layouts_except]' parameters.Check Version:
Check appRain CMF version in administration panel or configuration files.Verify Fix Applied:
After patching, test the same endpoint with XSS payloads to ensure they are properly sanitized or rejected.📡 Detection & Monitoring
Log Indicators:
- Unusual POST requests to /apprain/developer/addons/update/commonresource with script tags or JavaScript in parameters
- Multiple failed login attempts followed by successful authentication and access to developer features
Network Indicators:
- HTTP requests containing script tags or JavaScript code in the 'data[Addon][layouts]' or 'data[Addon][layouts_except]' parameters
SIEM Query:
source="web_server" AND uri="/apprain/developer/addons/update/commonresource" AND (param="data[Addon][layouts]" OR param="data[Addon][layouts_except]") AND (content="<script>" OR content="javascript:")