CVE-2022-47374
📋 TL;DR
This vulnerability affects multiple Siemens industrial control systems and allows attackers to send specially crafted HTTP(S) requests to exhaust system resources, causing denial of service. The affected devices include SIMATIC PC-Station Plus, S7-400 CPUs, SINAMICS S120 drives, and their SIPLUS variants. Organizations using these industrial automation products in critical infrastructure or manufacturing environments are at risk.
💻 Affected Systems
- SIMATIC PC-Station Plus
- SIMATIC S7-400 CPU 412-2 PN V7
- SIMATIC S7-400 CPU 414-3 PN/DP V7
- SIMATIC S7-400 CPU 414F-3 PN/DP V7
- SIMATIC S7-400 CPU 416-3 PN/DP V7
- SIMATIC S7-400 CPU 416F-3 PN/DP V7
- SINAMICS S120
- SIPLUS S7-400 CPU 414-3 PN/DP V7
- SIPLUS S7-400 CPU 416-3 PN/DP V7
📦 What is this software?
Simatic Pc Station Plus Firmware by Siemens
⚠️ Risk & Real-World Impact
Worst Case
Complete system unavailability leading to production shutdown, safety system failures, or process disruption in industrial environments.
Likely Case
Temporary denial of service affecting specific device functionality, potentially disrupting industrial operations until manual intervention.
If Mitigated
Limited impact with proper network segmentation and monitoring, allowing quick detection and response to attack attempts.
🎯 Exploit Status
The vulnerability requires sending HTTP(S) requests to the web server, which is relatively simple to execute. No authentication is required.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: V5.2 SP3 HF15 for SINAMICS S120; other products require firmware updates as specified in Siemens advisories
Vendor Advisory: https://cert-portal.siemens.com/productcert/pdf/ssa-892915.pdf
Restart Required: Yes
Instructions:
1. Download appropriate firmware updates from Siemens Support. 2. Follow Siemens update procedures for each affected device. 3. Apply updates during maintenance windows. 4. Restart devices as required. 5. Verify functionality post-update.
🔧 Temporary Workarounds
Network Segmentation
allIsolate affected devices in separate network segments with strict firewall rules limiting HTTP(S) access.
Disable Web Server
allIf web interface functionality is not required, disable the web server on affected devices.
🧯 If You Can't Patch
- Implement strict network access controls to limit HTTP(S) traffic to affected devices from trusted sources only.
- Deploy network monitoring and intrusion detection systems to detect and alert on abnormal HTTP request patterns.
🔍 How to Verify
Check if Vulnerable:
Check device firmware versions against affected versions list. For SINAMICS S120, verify version is < V5.2 SP3 HF15.Check Version:
Device-specific commands vary by product; typically accessed via device web interface or management software like TIA Portal.Verify Fix Applied:
Confirm firmware version meets patched requirements. Test web server functionality with normal operations.📡 Detection & Monitoring
Log Indicators:
- Unusual volume of HTTP requests to device web interfaces
- Device resource exhaustion alerts
- Web server error logs showing malformed requests
Network Indicators:
- High volume of HTTP(S) traffic to industrial control system devices
- Abnormal request patterns to device web servers
SIEM Query:
source="industrial_device" AND (http_request_count > threshold OR http_error_rate > threshold)