NVIDIA Hopper HGX for 8-GPU contains a vulnerability in the HGX Management Controller (HMC) that may allow a malicious actor with administrative access on the BMC to access the HMC as an administrator. A successful exploit of this vulnerability may lead to code execution, denial of service, escalation of privileges, information disclosure, and data tampering.
The product uses physical debug or test interfaces with support for multiple access levels, but it assigns the wrong debug access level to an internal asset, providing unintended access to the asset from untrusted debug agents.
Debug authorization can have multiple levels of access, defined such that different system internal assets are accessible based on the current authorized debug level. Other than debugger authentication (e.g., using passwords or challenges), the authorization can also be based on the system state or boot stage. For example, full system debug access might only be allowed early in boot after a system reset to ensure that previous session data is not accessible to the authenticated debugger. If this protection mechanism does not ensure that internal assets have the correct debug access level during each boot stage or change in system state, an attacker could obtain sensitive information from the internal asset using a debugger.