CVE-2023-36749
📋 TL;DR
This vulnerability affects Siemens RUGGEDCOM ROX industrial routers by supporting insecure TLS 1.0 protocol in their webserver. Attackers can perform man-in-the-middle attacks to intercept and manipulate data transmitted to/from these devices. Organizations using affected RUGGEDCOM ROX models with versions below V2.16.0 are at risk.
💻 Affected Systems
- RUGGEDCOM ROX MX5000
- RUGGEDCOM ROX MX5000RE
- RUGGEDCOM ROX RX1400
- RUGGEDCOM ROX RX1500
- RUGGEDCOM ROX RX1501
- RUGGEDCOM ROX RX1510
- RUGGEDCOM ROX RX1511
- RUGGEDCOM ROX RX1512
- RUGGEDCOM ROX RX1524
- RUGGEDCOM ROX RX1536
- RUGGEDCOM ROX RX5000
📦 What is this software?
Ruggedcom Rox Mx5000re Firmware by Siemens
⚠️ Risk & Real-World Impact
Worst Case
Complete compromise of device management communications, credential theft, configuration manipulation leading to industrial network disruption, and potential lateral movement into operational technology environments.
Likely Case
Interception of administrative credentials and configuration data during management sessions, enabling unauthorized access to industrial network devices.
If Mitigated
Limited impact with proper network segmentation, encrypted management channels, and monitoring for anomalous TLS connections.
🎯 Exploit Status
TLS 1.0 downgrade attacks are well-documented and tools for man-in-the-middle attacks are widely available. Exploitation requires network position to intercept traffic.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: V2.16.0
Vendor Advisory: https://cert-portal.siemens.com/productcert/pdf/ssa-146325.pdf
Restart Required: Yes
Instructions:
1. Download firmware V2.16.0 or later from Siemens support portal. 2. Backup current device configuration. 3. Upload and install new firmware via web interface or CLI. 4. Reboot device. 5. Verify TLS 1.0 is disabled in webserver settings.
🔧 Temporary Workarounds
Disable TLS 1.0 via Configuration
allManually configure webserver to disable TLS 1.0 and only allow TLS 1.2 or higher
Network Segmentation
allIsolate affected devices in separate VLANs with strict firewall rules limiting management access
🧯 If You Can't Patch
- Implement network-level TLS inspection/proxy that forces TLS 1.2+ for connections to affected devices
- Use VPN tunnels for all management access to encrypt traffic before it reaches vulnerable TLS endpoints
🔍 How to Verify
Check if Vulnerable:
Check device firmware version via web interface or CLI. If version is below V2.16.0, device is vulnerable. Also test with SSL/TLS scanners like testssl.sh or Nmap scripts.Check Version:
Login to device CLI and run 'show version' or check via web interface System Information pageVerify Fix Applied:
After patching to V2.16.0+, verify firmware version and test TLS connections to confirm TLS 1.0 is rejected and only TLS 1.2+ is accepted.📡 Detection & Monitoring
Log Indicators:
- Failed TLS handshake attempts indicating downgrade attacks
- Multiple connection attempts with different TLS versions
- Unusual source IPs attempting HTTPS connections
Network Indicators:
- TLS 1.0 ClientHello packets to device management IPs
- SSL/TLS version negotiation patterns suggesting downgrade attacks
SIEM Query:
source_ip="device_management_ip" AND (tls.version="TLSv1" OR ssl.version=0x0301)