Mitsubishi Electric CNC Denial-of-Service Vulnerability

A denial-of-service vulnerability has been identified in various series of Mitsubishi Electric CNC machines, including the M800V, M80V, M800, M80, E80, C80, M700V, M70V, E70 series, as well as the software tools NC Trainer2 and NC Trainer2 plus. This vulnerability arises from improper validation of input indices, positions, or offsets, allowing remote attackers to send specially crafted packets to TCP port 683. This exploitation causes out-of-bounds memory reads, leading to a denial-of-service condition where the affected system may enter an emergency shutdown, requiring a manual reset for recovery.

Impact

Exploitation of this vulnerability causes the CNC system to experience an out-of-bounds memory read, resulting in a denial-of-service condition. The system may enter an emergency shutdown, and a reset is required to restore normal operation.

Remediation

Users of affected products should contact their local Mitsubishi Electric representative to obtain and apply the fixed version, if available. For products without a fixed version, Mitsubishi Electric recommends using firewalls or VPNs to block unauthorized access, restricting physical access to the devices, and installing antivirus software on connected computers. Additionally, users can consult the product-specific instruction manuals for guidance on using the IP filter function to block access from untrusted hosts.