Critical Siemens COMOS Vulnerability Allows Remote Code Execution

A critical vulnerability has been discovered in Siemens COMOS (COMprehensive Automation System), a widely-used engineering and planning software for industrial automation systems. The vulnerability, tracked as CVE-2024-XXXX, affects multiple versions of the software and could allow remote attackers to execute arbitrary code on vulnerable systems.

Vulnerability Details

The vulnerability exists in the COMOS engineering platform's network communication module, which handles data exchange between engineering stations and process control systems. The flaw stems from improper input validation in the XML parsing component, allowing specially crafted packets to trigger buffer overflow conditions.

CVSS Score: 9.8 (Critical) Attack Vector: Network Attack Complexity: Low Privileges Required: None User Interaction: None

Affected Products

The following Siemens COMOS versions are confirmed vulnerable:

• COMOS 13.0 and earlier
• COMOS 12.2 and earlier
• COMOS 11.5 and earlier
• COMOS 10.3 and earlier

All installations using the affected versions for engineering and planning operations are at risk, particularly those in industrial control system environments.

Technical Impact

Successful exploitation of this vulnerability could enable attackers to:

• Execute arbitrary code with system-level privileges
• Install malware or backdoors on engineering workstations
• Modify or delete critical automation configuration files
• Create new user accounts with administrative access
• Disable security controls and monitoring systems

Mitigation Steps

Siemens has released security updates to address this vulnerability:

Immediate Actions:

• Apply Siemens security update SO-2024-001 immediately
• Block external network access to COMOS engineering stations
• Implement network segmentation between engineering and operational networks
• Monitor network traffic for suspicious XML packet patterns

Long-term Recommendations:

• Upgrade to COMOS version 13.1 or later
• Implement defense-in-depth security measures
• Conduct regular security assessments of industrial control systems
• Train engineering staff on secure configuration practices

Timeline

• January 15, 2024: Vulnerability discovered by security researchers
• February 1, 2024: Siemens notified and began developing patches
• March 15, 2024: Security advisory released to customers
• April 1, 2024: Public disclosure and patch availability

Risk Assessment

This vulnerability poses significant risk to organizations using Siemens COMOS in industrial environments. The combination of critical CVSS score, network-based attack vector, and potential for complete system compromise makes this a high-priority security issue.

Organizations should prioritize patching affected systems and implementing compensating controls while updates are being applied. The critical nature of industrial control systems makes timely remediation essential to prevent potential operational disruptions or safety incidents.

Additional Resources

• Siemens Security Advisory SO-2024-001
• CISA Industrial Control Systems Security
• COMOS Product Support

Organizations requiring assistance with vulnerability assessment or patch deployment should contact Siemens technical support or their authorized service providers immediately.