High · published September 20, 2022
An attacker can exploit this vulnerability to elevate privileges from ring 0 to ring -2, execute arbitrary code in System Management Mode - an environment more privileged than operating system (OS) and completely isolated from it. Running arbitrary code in SMM additionally bypasses SMM-based SPI flash protections against modifications, which can help an attacker to install a firmware backdoor/implant into BIOS. Such a malicious firmware code in BIOS could persist across operating system re-installs. Additionally, this vulnerability potentially could be used by malicious actors to bypass security mechanisms provided by UEFI firmware (for example, Secure Boot and some types of memory isolation for hypervisors). This issue affects: Module name: OverClockSmiHandler SHA256: a204699576e1a48ce915d9d9423380c8e4c197003baf9d17e6504f0265f3039c Module GUID: 4698C2BD-A903-410E-AD1F-5EEF3A1AE422