CVE-2020-27261
📋 TL;DR
CVE-2020-27261 is a stack-based buffer overflow vulnerability in Omron CX-One industrial automation software that allows remote attackers to execute arbitrary code on affected systems. This affects organizations using Omron CX-One Version 4.60 and earlier for industrial control systems. Successful exploitation could lead to complete system compromise and disruption of industrial operations.
💻 Affected Systems
- Omron CX-One
📦 What is this software?
Cx One by Omron
⚠️ Risk & Real-World Impact
Worst Case
Complete system takeover allowing attacker to execute arbitrary code, disrupt industrial processes, manipulate control systems, and potentially cause physical damage or safety incidents.
Likely Case
Remote code execution leading to industrial control system compromise, data theft, operational disruption, and lateral movement within industrial networks.
If Mitigated
Limited impact if systems are properly segmented, monitored, and have network controls preventing unauthorized access to vulnerable services.
🎯 Exploit Status
Multiple advisories from ZDI and CISA indicate weaponization is likely given the critical nature and remote exploitation capability.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Version 4.61 or later
Vendor Advisory: https://www.omron.com/global/en/
Restart Required: Yes
Instructions:
1. Download CX-One Version 4.61 or later from Omron's official website. 2. Uninstall the vulnerable version. 3. Install the updated version. 4. Restart the system.
🔧 Temporary Workarounds
Network Segmentation
allIsolate Omron CX-One systems from untrusted networks and internet access
Firewall Rules
allImplement strict firewall rules to limit access to CX-One systems only from authorized engineering stations
🧯 If You Can't Patch
- Implement strict network segmentation to isolate vulnerable systems
- Deploy intrusion detection systems and monitor for exploitation attempts
🔍 How to Verify
Check if Vulnerable:
Check CX-One version in Help > About CX-One menu. If version is 4.60 or earlier, system is vulnerable.Check Version:
Check via CX-One GUI: Help > About CX-OneVerify Fix Applied:
Verify version is 4.61 or later in Help > About CX-One menu after update.📡 Detection & Monitoring
Log Indicators:
- Unusual network connections to CX-One ports
- Process creation anomalies from CX-One executables
- Failed authentication attempts to industrial systems
Network Indicators:
- Unusual traffic patterns to/from CX-One systems
- Exploit attempt signatures in network traffic
- Unexpected protocol communications
SIEM Query:
source="cx-one" OR process="CXONE*" AND (event_type="process_creation" OR event_type="network_connection")🔗 References
- https://us-cert.cisa.gov/ics/advisories/icsa-21-007-02
- https://www.zerodayinitiative.com/advisories/ZDI-21-183/
- https://www.zerodayinitiative.com/advisories/ZDI-21-185/
- https://us-cert.cisa.gov/ics/advisories/icsa-21-007-02
- https://www.zerodayinitiative.com/advisories/ZDI-21-183/
- https://www.zerodayinitiative.com/advisories/ZDI-21-185/
