CVE-2025-22926
📋 TL;DR
This vulnerability allows attackers to perform directory traversal attacks by sending a specially crafted POST request to the openSIS messaging module. Attackers can potentially read, write, or delete files outside the intended directory. All openSIS installations running versions 8.0 through 9.1 are affected.
💻 Affected Systems
- OS4ED openSIS Classic
📦 What is this software?
Opensis by Os4ed
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise through arbitrary file write leading to remote code execution, sensitive data exposure, or system destruction.
Likely Case
Unauthorized file access leading to data theft, configuration file manipulation, or privilege escalation.
If Mitigated
Limited impact with proper file permissions, web application firewalls, and input validation in place.
🎯 Exploit Status
Exploitation requires authentication to access the messaging module. The vulnerability is in the file upload/save functionality.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Not available
Vendor Advisory: Not available
Restart Required: No
Instructions:
1. Monitor OS4ED for official patches or updates. 2. Apply patches immediately when available. 3. Test in development environment before production deployment.
🔧 Temporary Workarounds
Disable vulnerable endpoint
allTemporarily disable or restrict access to the vulnerable messaging module endpoint
# Add to .htaccess for Apache:
RewriteRule ^Modules\.php\?modname=messaging/Inbox\.php.*$ - [F,L]
# For Nginx:
location ~* ^/Modules\.php\?modname=messaging/Inbox\.php { deny all; }
Implement WAF rules
allConfigure web application firewall to block directory traversal patterns
# ModSecurity rule:
SecRule ARGS:filename "@contains .." "id:1001,phase:2,deny,msg:'Directory Traversal Attempt'"
# Cloudflare WAF: Enable OWASP ruleset with directory traversal protection
🧯 If You Can't Patch
- Implement strict file permission controls on the web server to limit write access
- Deploy network segmentation to isolate openSIS from critical systems
🔍 How to Verify
Check if Vulnerable:
Test by attempting to access /Modules.php?modname=messaging/Inbox.php&modfunc=save&filename=../../../etc/passwd with authenticated sessionCheck Version:
Check openSIS version in admin panel or review installation files for version markersVerify Fix Applied:
Verify the patch prevents directory traversal by testing with malicious filename parameters📡 Detection & Monitoring
Log Indicators:
- POST requests to /Modules.php with modname=messaging/Inbox.php and filename parameter containing '..' or '../'
- File access errors for paths outside web root
Network Indicators:
- HTTP POST requests with filename parameters containing directory traversal sequences
- Unusual file access patterns from web server process
SIEM Query:
source="web_logs" AND uri_path="/Modules.php" AND query_string="*modname=messaging/Inbox.php*" AND (query_string="*filename=..*" OR query_string="*filename=../*")