NVIDIA DGX-1 - SBIOS / SMM firmware: An out-of-bounds access in the Ofbd handler in the AMI SBIOS reaches SMM code
Impact
An out-of-bounds access in the Ofbd handler in the AMI SBIOS reaches SMM code execution against a preconditioned heap, with scope extending to other components. This is firmware-level persistence: it survives OS reinstall, image re-flash and tenant handoff, and it is invisible to anything running above it. On a bare-metal GPU rental business it is the difference between wiping a node between tenants and not actually being able to.
Who can reach it
Local and already privileged - host root, or code that has reached the platform firmware/SMM path. It is not a first foothold; it is what turns a one-time root compromise into something you cannot remediate by reimaging.
What to do
Flash the fixed SBIOS from bulletin 5458. Cost: not live-patchable. Full node drain, host power cycle, and on DGX the SBIOS ships inside a firmware bundle alongside BMC and CPLD components, so budget 30-60 minutes of node downtime plus a post-flash health check. Firmware rollback protection means you cannot cleanly revert - stage on one node before the fleet.
References
Related entries
- NVIDIA DGX-1 - SBIOS / SMM firmware: A flaw in the Bds phase reaches firmware code execution and privilege escalationCVE-2023-25509 · NVIDIA DGX-1 - SBIOS / SMM firmwareMedium
- NVIDIA DGX-1 - SBIOS / SMM firmware: The Uncore PEI module never authenticates the code executed by SSA, soCVE-2023-0209 · NVIDIA DGX-1 - SBIOS / SMM firmwareHigh
- DGX A100 / A800 SBIOS: Code execution + privesc in SBIOSCVE-2023-25521 · DGX A100 / A800 SBIOSHigh
- DGX A100 / A800 SBIOS: DoS / data tampering / info disclosureCVE-2023-25522 · DGX A100 / A800 SBIOSHigh
- Cumulus Linux (switch OS): Cross-tenant info disclosure (VxLAN IPv6 mis-forwarding on SVI)CVE-2023-25525 · Cumulus Linux (switch OS)High
- DGX A100 SBIOS: Improper crypto config / UI-layer restriction in SBIOSCVE-2023-31032 · DGX A100 SBIOSHigh
This entry is curated: imported from vendor advisories with machine assistance, not yet individually verified. Confirm against your vendor's advisory before acting, and report anything wrong.