Description
A vulnerability in the Software SMI handler (SwSmiInputValue 0x20) allows a local attacker to supply a crafted pointer (FuncBlock) through RBX and RCX register values. This pointer is passed unchecked into multiple flash management functions (ReadFlash, WriteFlash, EraseFlash, and GetFlashInfo) that dereference both the structure and its nested members, such as BufAddr. This enables arbitrary read/write access to System Management RAM (SMRAM), allowing an attacker to corrupt firmware memory, exfiltrate SMRAM content via flash, or install persistent implants.
Metrics
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HAffected software
No affected versions have been published.
Timeline
- Published
- Jul 11, 2025
- Last modified
- Jun 17, 2026
- NVD status
- Deferred