CVE-2021-30188
📋 TL;DR
CVE-2021-30188 is a critical stack-based buffer overflow vulnerability in CODESYS V2 runtime systems. It allows remote attackers to execute arbitrary code on affected industrial control systems. Organizations using CODESYS V2 runtime for industrial automation are affected.
💻 Affected Systems
- CODESYS V2 runtime system SP
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise leading to remote code execution, potential disruption of industrial processes, and lateral movement within operational technology networks.
Likely Case
Remote code execution allowing attackers to manipulate industrial processes, steal sensitive data, or disrupt operations.
If Mitigated
Limited impact if systems are isolated, patched, and have proper network segmentation with industrial firewall rules.
🎯 Exploit Status
Buffer overflow vulnerabilities in industrial control systems are frequently targeted. CVSS 9.8 suggests straightforward exploitation.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 2.4.7.55 or later
Vendor Advisory: https://customers.codesys.com/index.php?eID=dumpFile&t=f&f=14725&token=08691519ef764b252630759eff925890176ecd78&download=
Restart Required: Yes
Instructions:
1. Download patch from CODESYS customer portal. 2. Backup current configuration. 3. Install update following vendor instructions. 4. Restart affected systems. 5. Verify patch installation.
🔧 Temporary Workarounds
Network Segmentation
allIsolate CODESYS systems from untrusted networks using industrial firewalls and VLANs.
Access Control Restrictions
allImplement strict network access controls to limit connections to CODESYS runtime systems.
🧯 If You Can't Patch
- Implement strict network segmentation to isolate affected systems from all untrusted networks.
- Deploy industrial intrusion detection systems to monitor for exploitation attempts.
🔍 How to Verify
Check if Vulnerable:
Check CODESYS runtime version via CODESYS development environment or system properties.Check Version:
Check via CODESYS IDE: Project → Target Settings → Device → VersionVerify Fix Applied:
Verify version is 2.4.7.55 or later in CODESYS development environment.📡 Detection & Monitoring
Log Indicators:
- Unusual network connections to CODESYS ports (1200, 1217)
- Abnormal process creation on industrial controllers
- Memory access violations in system logs
Network Indicators:
- Unexpected traffic to CODESYS runtime ports from unauthorized sources
- Malformed packets targeting CODESYS services
SIEM Query:
source_port=1200 OR source_port=1217 AND (event_type="buffer_overflow" OR event_type="memory_violation")🔗 References
- https://customers.codesys.com/index.php
- https://customers.codesys.com/index.php?eID=dumpFile&t=f&f=14725&token=08691519ef764b252630759eff925890176ecd78&download=
- https://customers.codesys.com/index.php
- https://customers.codesys.com/index.php?eID=dumpFile&t=f&f=14725&token=08691519ef764b252630759eff925890176ecd78&download=
