CVE-2018-11466
📋 TL;DR
A critical vulnerability in Siemens SINUMERIK CNC systems allows remote attackers to send specially crafted packets to port 102/tcp, potentially causing denial-of-service or remote code execution in the software firewall. This affects multiple SINUMERIK product lines including 808D, 828D, and 840D sl systems. Attackers with network access to vulnerable systems can exploit this without authentication or user interaction.
💻 Affected Systems
- SINUMERIK 808D
- SINUMERIK 828D
- SINUMERIK 840D sl
📦 What is this software?
Sinumerik 840d Sl V4.7 Firmware by Siemens
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete system compromise, allowing attackers to manipulate CNC operations, steal sensitive industrial data, or cause physical damage to manufacturing equipment.
Likely Case
Denial-of-service condition disrupting manufacturing operations, potentially causing production downtime and financial losses.
If Mitigated
Limited impact if systems are properly segmented and access to port 102/tcp is restricted to trusted networks only.
🎯 Exploit Status
No public exploit code was known at advisory publication, but the vulnerability is unauthenticated and network-accessible, making exploitation relatively straightforward for skilled attackers.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 808D: No patch available (consider upgrading), 828D: V4.7 SP6 HF1, 840D sl: V4.7 SP6 HF5 or V4.8 SP3
Vendor Advisory: https://cert-portal.siemens.com/productcert/pdf/ssa-170881.pdf
Restart Required: Yes
Instructions:
1. Download appropriate firmware updates from Siemens support portal. 2. Backup current configuration. 3. Apply firmware update following Siemens documentation. 4. Restart affected systems. 5. Verify successful update.
🔧 Temporary Workarounds
Network Segmentation
allRestrict access to port 102/tcp using firewall rules to only trusted networks and devices.
Disable Unnecessary Services
allIf ISO-TSAP service on port 102 is not required, disable it completely.
🧯 If You Can't Patch
- Implement strict network segmentation to isolate SINUMERIK systems from untrusted networks
- Deploy intrusion detection systems to monitor for anomalous traffic on port 102/tcp
🔍 How to Verify
Check if Vulnerable:
Check SINUMERIK system version against affected versions list. Use network scanning tools to verify port 102/tcp is accessible.Check Version:
Check version through SINUMERIK HMI interface or diagnostic tools specific to each product line.Verify Fix Applied:
Verify system version is updated to patched versions: 828D V4.7 SP6 HF1 or higher, 840D sl V4.7 SP6 HF5 or higher, or V4.8 SP3 or higher.📡 Detection & Monitoring
Log Indicators:
- Unusual connection attempts to port 102/tcp
- Firewall service crashes or restarts
- Anomalous network traffic patterns
Network Indicators:
- Malformed packets to port 102/tcp
- Unexpected connections from untrusted sources to port 102
SIEM Query:
source_port:102 AND (packet_size:anomalous OR protocol_violation:true)