CVE-2025-34081
📋 TL;DR
The CONPROSYS HMI System exposes an unauthenticated PHP phpinfo() debug page that reveals sensitive system information. This vulnerability affects all CONPROSYS HMI System (CHS) installations before version 3.7.7. Attackers can use the exposed information to gather intelligence for further attacks.
💻 Affected Systems
- Contec Co.,Ltd. CONPROSYS HMI System (CHS)
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Attackers obtain sensitive system configuration, environment variables, database credentials, and file paths, enabling full system compromise through follow-up attacks.
Likely Case
Information disclosure provides attackers with reconnaissance data to plan targeted attacks against the HMI system or connected industrial control systems.
If Mitigated
Limited information exposure with no direct path to system compromise, though reconnaissance data may still be obtained.
🎯 Exploit Status
Direct access to phpinfo() page requires no special exploitation; information gathering is trivial.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 3.7.7
Vendor Advisory: https://jvn.jp/en/vu/JVNVU92266386/
Restart Required: Yes
Instructions:
1. Download CONPROSYS HMI System version 3.7.7 or later from Contec. 2. Backup current configuration. 3. Install the update following vendor instructions. 4. Restart the system. 5. Verify the phpinfo() page is no longer accessible.
🔧 Temporary Workarounds
Block access to phpinfo.php
linuxUse web server configuration to deny access to the debug page.
# For Apache: add to .htaccess or virtual host config
<Files "phpinfo.php">
Order allow,deny
Deny from all
</Files>
# For Nginx: add to server block
location = /phpinfo.php {
deny all;
return 403;
}
Remove phpinfo.php file
linuxDelete the exposed debug page file from the web root.
rm /path/to/webroot/phpinfo.php
🧯 If You Can't Patch
- Isolate the CONPROSYS system behind a firewall with strict network segmentation.
- Implement web application firewall (WAF) rules to block access to phpinfo.php and similar debug endpoints.
🔍 How to Verify
Check if Vulnerable:
Access http://<CONPROSYS_IP>/phpinfo.php in a web browser; if it loads a PHP information page, the system is vulnerable.Check Version:
Check system web interface or contact vendor for version information; no standard CLI command available.Verify Fix Applied:
Attempt to access http://<CONPROSYS_IP>/phpinfo.php; it should return 403/404 error or be inaccessible.📡 Detection & Monitoring
Log Indicators:
- HTTP GET requests to /phpinfo.php from unauthorized IPs
- Increased scanning activity to the CONPROSYS system
Network Indicators:
- Unusual outbound connections from CONPROSYS system following access to phpinfo.php
- Traffic patterns suggesting reconnaissance
SIEM Query:
source="web_logs" AND url="/phpinfo.php" AND response_code=200