CVE-2023-54327
📋 TL;DR
CVE-2023-54327 is an authentication bypass vulnerability in Tinycontrol LAN Controller 1.58a that allows unauthenticated attackers to change administrative passwords via a crafted API request to the /stm.cgi endpoint. This affects organizations using Tinycontrol LAN Controller for network device management, potentially giving attackers full administrative control over affected systems.
💻 Affected Systems
- Tinycontrol LAN Controller
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Attackers gain full administrative control over the LAN controller, enabling them to reconfigure network devices, intercept traffic, deploy malware, or disrupt network operations entirely.
Likely Case
Attackers change admin credentials to gain persistent access, then use the compromised controller to manipulate connected network devices or exfiltrate sensitive network configuration data.
If Mitigated
With proper network segmentation and access controls, impact is limited to the controller itself, though attackers could still disrupt controller functionality.
🎯 Exploit Status
Exploit code is publicly available on Exploit-DB (ID 51732) and requires only basic HTTP request crafting skills.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: https://www.tinycontrol.pl
Restart Required: No
Instructions:
No official patch available. Check vendor website for updates. Consider upgrading to a newer version if available or implementing workarounds.
🔧 Temporary Workarounds
Network Access Restriction
linuxRestrict access to the Tinycontrol LAN Controller management interface to trusted IP addresses only.
iptables -A INPUT -p tcp --dport [CONTROLLER_PORT] -s [TRUSTED_IP] -j ACCEPT
iptables -A INPUT -p tcp --dport [CONTROLLER_PORT] -j DROP
Web Server Configuration
allConfigure web server to block or restrict access to the /stm.cgi endpoint.
LocationMatch "^/stm\.cgi"
Order deny,allow
Deny from all
Allow from [TRUSTED_IP]
🧯 If You Can't Patch
- Isolate the Tinycontrol LAN Controller on a separate VLAN with strict access controls
- Implement network monitoring and alerting for unauthorized access attempts to the controller
🔍 How to Verify
Check if Vulnerable:
Send a crafted POST request to http://[CONTROLLER_IP]/stm.cgi with authentication bypass parameters and check if admin password can be changed without credentials.Check Version:
Check web interface login page or about page for version information, or use: curl -s http://[CONTROLLER_IP]/ | grep -i versionVerify Fix Applied:
Attempt the same exploit after implementing workarounds - access should be denied or restricted.📡 Detection & Monitoring
Log Indicators:
- Unusual POST requests to /stm.cgi endpoint
- Admin password change events from unexpected IP addresses
- Failed authentication attempts followed by successful admin actions
Network Indicators:
- HTTP POST requests to /stm.cgi with crafted authentication parameters
- Traffic to controller from unexpected sources
SIEM Query:
source="web_server" AND (url="/stm.cgi" OR url="*stm.cgi*") AND (method="POST" OR status="200") | stats count by src_ip🔗 References
- https://www.exploit-db.com/exploits/51732
- https://www.tinycontrol.pl
- https://www.vulncheck.com/advisories/tinycontrol-lan-controller-a-authentication-bypass-via-admin-password-change
- https://www.zeroscience.mk/en/vulnerabilities/ZSL-2023-5787.php
- https://www.zeroscience.mk/en/vulnerabilities/ZSL-2023-5787.php
