The OPC UA implementations (ANSI C and C++) in affected products contain an integer overflow vulnerability that could cause the application to run into an infinite loop during certificate validation. This could allow an unauthenticated remote attacker to create a denial of service condition by sending a specially crafted certificate.

Affected devices do not contain an Immutable Root of Trust in Hardware. With this the integrity of the code executed on the device can not be validated during load-time. An attacker with physical access to the device could use this to replace the boot image of the device and execute arbitrary code.