CVE-2021-29395
📋 TL;DR
This vulnerability allows remote attackers without authentication to download arbitrary files from the server filesystem by exploiting a directory traversal flaw in NorthStar Club Management software. It affects all systems running Northstar Technologies Inc NorthStar Club Management version 6.3. Attackers can access sensitive files including JSP source code, configuration files, and system files.
💻 Affected Systems
- Northstar Technologies Inc NorthStar Club Management
📦 What is this software?
Northstar Club Management by Globalnorthstar
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise through credential theft, source code analysis for further vulnerabilities, and potential lateral movement to other systems.
Likely Case
Theft of sensitive data including database credentials, user information, and proprietary source code leading to data breach.
If Mitigated
Limited impact if proper network segmentation and file system permissions prevent access to critical system files.
🎯 Exploit Status
Exploitation requires only web access to the vulnerable endpoint with directory traversal payloads.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: Not available
Restart Required: No
Instructions:
Contact Northstar Technologies for patch information. Consider upgrading to a newer version if available.
🔧 Temporary Workarounds
Block vulnerable endpoint
allConfigure web server or WAF to block access to /northstar/filemanager/download.jsp
# Apache: RewriteRule ^/northstar/filemanager/download\.jsp - [F]
# Nginx: location ~ ^/northstar/filemanager/download\.jsp { deny all; }
Implement input validation
allAdd input validation to reject directory traversal sequences in file parameters
🧯 If You Can't Patch
- Implement strict network access controls to limit access to the application
- Deploy web application firewall with directory traversal protection rules
🔍 How to Verify
Check if Vulnerable:
Attempt to access /northstar/filemanager/download.jsp?file=../../../../etc/passwd (or similar traversal) and check if file contents are returned.Check Version:
Check application version in web interface or configuration filesVerify Fix Applied:
Test the same directory traversal attempts after applying workarounds to confirm they are blocked.📡 Detection & Monitoring
Log Indicators:
- HTTP requests to /northstar/filemanager/download.jsp with ../ sequences in parameters
- Unusual file access patterns from web server process
Network Indicators:
- HTTP requests containing directory traversal patterns (../, ..\) to the vulnerable endpoint
SIEM Query:
source="web_server" AND uri_path="/northstar/filemanager/download.jsp" AND (uri_query="*../*" OR uri_query="*..\*")