CVE-2018-13808
📋 TL;DR
A vulnerability in Siemens CP 1604 and CP 1616 devices allows attackers with network access to port 23/tcp to extract internal communication data or cause Denial-of-Service conditions. This affects all versions of these industrial communication processors. Successful exploitation requires network access to vulnerable devices.
💻 Affected Systems
- Siemens CP 1604
- Siemens CP 1616
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete device compromise allowing data exfiltration of sensitive industrial communication data and permanent DoS rendering devices inoperable
Likely Case
Data leakage of internal communication data and temporary DoS affecting industrial operations
If Mitigated
Limited impact if devices are properly segmented and access controls are implemented
🎯 Exploit Status
No public exploitation known at advisory publication, but vulnerability is unauthenticated and requires only network access
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Contact Siemens for specific firmware updates
Vendor Advisory: https://cert-portal.siemens.com/productcert/pdf/ssa-559174.pdf
Restart Required: Yes
Instructions:
1. Contact Siemens support for firmware updates. 2. Download appropriate firmware version. 3. Apply firmware update following Siemens documentation. 4. Restart affected devices.
🔧 Temporary Workarounds
Network Segmentation
allIsolate affected devices in separate network segments with strict access controls
Disable Telnet Service
allDisable Telnet service on port 23/tcp if not required for operations
🧯 If You Can't Patch
- Implement strict network access controls to limit access to port 23/tcp
- Monitor network traffic to affected devices for suspicious Telnet connections
🔍 How to Verify
Check if Vulnerable:
Check if Siemens CP 1604 or CP 1616 devices are present in network and have Telnet service (port 23) accessibleCheck Version:
Check device firmware version through Siemens configuration tools or device management interfaceVerify Fix Applied:
Verify firmware version is updated per Siemens advisory and test that Telnet service no longer exposes vulnerability📡 Detection & Monitoring
Log Indicators:
- Unusual Telnet connection attempts to port 23
- Multiple failed connection attempts to industrial devices
Network Indicators:
- Unexpected traffic to port 23/tcp on industrial devices
- Telnet protocol anomalies
SIEM Query:
source_port:23 AND (device_type:industrial OR device_vendor:Siemens)