NVIDIA’s B300 MCU houses a CX8 microcontroller unit that can be exploited by a malicious actor to alter unsupported registry entries, producing a bad state. This manipulation can lead to both interruption of service and alteration of critical data stored within the MCU. The vulnerability is rooted in a flaw that allows unauthorized registry modification, a weakness that directly threatens system availability and integrity.

The flaw affects NVIDIA HGX and DGX B300 platforms, specifically the CX8 MCU component. No specific firmware or hardware revisions are listed in the CVE data, so all B300 systems using the affected MCU are potentially vulnerable until a vendor patch is applied.

The reported CVSS score of 5.9 indicates a moderate severity, and the EPSS score is not available, so the exact likelihood of exploitation cannot be quantified from the CVE report. The vulnerability is not included in the CISA KEV catalog, suggesting no publicly known exploits yet. Based on the description, the attack likely requires privileged access to the MCU—either through firmware update interfaces or a physically proximate attack vector. While remote exploitation is not explicitly stated, the ability to modify unsupported registries hints at a low‑to‑medium complexity attack that could be performed by an adversary with sufficient access to the device’s firmware management pathway.