CVE-2025-13261
📋 TL;DR
A path traversal vulnerability in the lsfusion platform allows attackers to manipulate the Version parameter in DownloadFileRequestHandler to access arbitrary files on the server. This affects lsfusion platform versions up to 6.1. Remote exploitation is possible without authentication.
💻 Affected Systems
- lsfusion platform
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Attackers could read sensitive system files, configuration files, or application data, potentially leading to credential theft, data exfiltration, or further system compromise.
Likely Case
Unauthorized access to application files, configuration files, or other files accessible to the web server process, potentially exposing sensitive information.
If Mitigated
Limited impact if proper file system permissions restrict web server access to sensitive directories and files.
🎯 Exploit Status
The exploit has been made public and requires minimal technical skill to execute. Remote exploitation is confirmed.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Version 6.2 or later
Vendor Advisory: https://github.com/lsfusion/platform/issues/1543
Restart Required: Yes
Instructions:
1. Upgrade lsfusion platform to version 6.2 or later. 2. Restart the lsfusion service. 3. Verify the fix by testing the vulnerable endpoint.
🔧 Temporary Workarounds
Input Validation Filter
allImplement input validation to reject path traversal sequences in the Version parameter
Configure web application firewall to block requests containing '../' or similar sequences
Access Restriction
allRestrict network access to the lsfusion web interface
Configure firewall rules to limit access to trusted IP addresses only
🧯 If You Can't Patch
- Implement strict file system permissions to limit what files the web server process can access
- Deploy a web application firewall (WAF) with path traversal protection rules
🔍 How to Verify
Check if Vulnerable:
Check if lsfusion version is 6.1 or earlier. Test by attempting to access files using path traversal in the Version parameter.Check Version:
Check the lsfusion version in the application interface or configuration filesVerify Fix Applied:
After upgrading to version 6.2+, test that path traversal attempts in the Version parameter are properly rejected.📡 Detection & Monitoring
Log Indicators:
- HTTP requests with suspicious Version parameter values containing '../' or similar sequences
- Failed file access attempts from web server process
Network Indicators:
- HTTP requests to DownloadFileRequestHandler endpoint with manipulated Version parameters
SIEM Query:
source="web_server_logs" AND (uri="*DownloadFileRequestHandler*" AND (param="*../*" OR param="*..\\*"))