CVE-2021-44221
📋 TL;DR
A remote attacker can exploit improper input validation in SIMATIC eaSie Core Package to cause denial of service. This affects all versions before V22.00 of Siemens' industrial automation software.
💻 Affected Systems
- SIMATIC eaSie Core Package
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete system unavailability disrupting industrial operations, potentially causing production downtime or safety issues in critical infrastructure.
Likely Case
Service disruption requiring manual restart of affected systems, impacting operational continuity.
If Mitigated
Minimal impact with proper network segmentation and monitoring allowing quick detection and response.
🎯 Exploit Status
Remote exploitation without authentication is possible due to improper input validation.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: V22.00 or later
Vendor Advisory: https://cert-portal.siemens.com/productcert/pdf/ssa-580125.pdf
Restart Required: Yes
Instructions:
1. Download V22.00 or later from Siemens support portal. 2. Backup current configuration. 3. Install update following Siemens documentation. 4. Restart affected systems.
🔧 Temporary Workarounds
Network Segmentation
allRestrict network access to affected systems to trusted sources only.
Firewall Rules
allImplement strict firewall rules to limit traffic to necessary ports and protocols.
🧯 If You Can't Patch
- Implement strict network segmentation and access controls
- Deploy intrusion detection systems and monitor for anomalous traffic patterns
🔍 How to Verify
Check if Vulnerable:
Check installed version of SIMATIC eaSie Core Package via Siemens management interface or system documentation.Check Version:
Check via Siemens TIA Portal or system management tools specific to SIMATIC products.Verify Fix Applied:
Confirm version is V22.00 or later through Siemens management interface.📡 Detection & Monitoring
Log Indicators:
- Unusual message passing framework errors
- System crash/restart events
- High volume of malformed input attempts
Network Indicators:
- Unexpected traffic to message passing framework ports
- Anomalous patterns in industrial protocol communications
SIEM Query:
source="industrial_system" AND (event_type="crash" OR error_message="message_passing_framework")