CVE-2025-40670
📋 TL;DR
An incorrect authorization vulnerability in TCMAN's GIM v11 allows unauthenticated attackers to create privileged user accounts via a POST request to /PC/frmGestionUser.aspx/updateUser. This enables privilege escalation and unauthorized system access. Organizations using TCMAN GIM v11 are affected.
💻 Affected Systems
- TCMAN GIM
📦 What is this software?
Gim by Tcman
⚠️ Risk & Real-World Impact
Worst Case
Attacker creates administrative user, gains full system control, and potentially compromises the entire TCMAN GIM environment and connected systems.
Likely Case
Attacker creates privileged user to access sensitive data, modify configurations, or disrupt operations within the GIM platform.
If Mitigated
With proper network segmentation and monitoring, impact is limited to the GIM application with detection of unauthorized user creation.
🎯 Exploit Status
Simple HTTP POST request to known endpoint. No authentication required. Attack can be automated with basic tools.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: https://www.incibe.es/en/incibe-cert/notices/aviso/multiple-vulnerabilities-tcman-gim-1
Restart Required: Yes
Instructions:
1. Contact TCMAN vendor for patch availability. 2. Apply vendor-provided security update. 3. Restart GIM services. 4. Verify fix by testing exploit path.
🔧 Temporary Workarounds
Network Access Control
windowsRestrict access to GIM web interface using firewall rules or network segmentation.
# Example Windows Firewall rule: New-NetFirewallRule -DisplayName "Block GIM External" -Direction Inbound -Protocol TCP -LocalPort 80,443 -RemoteAddress Internet -Action Block
Web Application Firewall
allDeploy WAF to block requests to /PC/frmGestionUser.aspx/updateUser endpoint.
# WAF rule example: deny POST requests containing '/PC/frmGestionUser.aspx/updateUser' in URI
🧯 If You Can't Patch
- Isolate TCMAN GIM server in separate network segment with strict access controls
- Implement monitoring and alerting for user creation events and suspicious POST requests to the vulnerable endpoint
🔍 How to Verify
Check if Vulnerable:
Attempt to send POST request to http(s)://[GIM_SERVER]/PC/frmGestionUser.aspx/updateUser with user creation payload. If successful without authentication, system is vulnerable.Check Version:
Check GIM version in web interface or consult application documentation for version identification.Verify Fix Applied:
Repeat exploit attempt after remediation. Successful fix should return authorization error or block the request.📡 Detection & Monitoring
Log Indicators:
- POST requests to /PC/frmGestionUser.aspx/updateUser
- Unexpected user creation events
- Failed authentication attempts followed by successful user creation
Network Indicators:
- HTTP POST to vulnerable endpoint from unauthorized IPs
- Unusual traffic patterns to GIM web interface
SIEM Query:
source="web_server" AND (uri="/PC/frmGestionUser.aspx/updateUser" OR method="POST" AND uri CONTAINS "frmGestionUser")