CVE-2025-3087
📋 TL;DR
CVE-2025-3087 is a stored cross-site scripting (XSS) vulnerability in M-Files Web versions 25.1.14445.5 through 25.2.14524.4. It allows authenticated users to inject malicious scripts that execute in other users' browsers when viewing affected content. This affects organizations using vulnerable M-Files Web deployments.
💻 Affected Systems
- M-Files Web
📦 What is this software?
M Files Web by M Files
⚠️ Risk & Real-World Impact
Worst Case
An attacker could steal session cookies, perform actions as other users, deface the application, or redirect users to malicious sites, potentially leading to full account compromise and data theft.
Likely Case
Attackers with valid credentials could inject malicious scripts to steal session tokens or credentials from other users, leading to unauthorized access to sensitive documents and metadata.
If Mitigated
With proper input validation and output encoding, the risk is limited to authenticated users only, reducing the attack surface compared to unauthenticated XSS.
🎯 Exploit Status
Exploitation requires authenticated access; stored XSS typically has low complexity once the injection point is identified.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 25.2.14524.5 and later
Vendor Advisory: https://product.m-files.com/security-advisories/cve-2025-3087/
Restart Required: Yes
Instructions:
1. Download the latest M-Files Web version from the vendor portal. 2. Backup current configuration and data. 3. Install the update following vendor documentation. 4. Restart the M-Files Web service. 5. Verify the update applied successfully.
🔧 Temporary Workarounds
Implement Content Security Policy (CSP)
allAdd a strict CSP header to prevent script execution from untrusted sources.
Add 'Content-Security-Policy: default-src 'self'; script-src 'self'' to web server configuration
Restrict User Permissions
allLimit authenticated users' ability to create or modify content that could contain scripts.
🧯 If You Can't Patch
- Implement web application firewall (WAF) rules to block XSS payloads
- Enable input validation and output encoding at the application layer
🔍 How to Verify
Check if Vulnerable:
Check the M-Files Web version in the administration interface or configuration files against the affected range.Check Version:
Check the web interface or configuration files for version information; no single command applies to all deployments.Verify Fix Applied:
Confirm the version is 25.2.14524.5 or later and test for XSS by attempting to inject a benign script (e.g., <script>alert('test')</script>) in user-controllable fields.📡 Detection & Monitoring
Log Indicators:
- Unusual POST requests with script tags or JavaScript in parameters
- Multiple failed login attempts followed by successful authentication and content modification
Network Indicators:
- HTTP requests containing script tags or encoded JavaScript in user input fields
- Outbound connections to unknown domains following user interactions
SIEM Query:
source="m-files-web" AND (http_method="POST" AND (url="*<script>*" OR param="*javascript:*"))