asfenbg.blogg.se - Islide into heaven

ISLIDE INTO HEAVEN CODE
ISLIDE INTO HEAVEN SERIES
ISLIDE INTO HEAVEN WINDOWS

The wh* functions expand the function arguments to make them compatible for 64-bit API calls.Putting everything in its place and finding the right syscall.Getting arguments from the stack to the registers.Expanding variables – from 32-bit to 64-bit.

ISLIDE INTO HEAVEN CODE

Some not very interesting code is running at this stage… Let’s take the jump and see where it leads us….From here on we canĬommunicate with 64-bit function and send syscalls. This jmp makes the processor switch to 圆4.Up to here the processor ran in x86 mode.

ISLIDE INTO HEAVEN WINDOWS

In every process on 64-bit windows there are 2 code segments:.Its purpose is to perform the transition from The export function Wow64Transition points to The API function doesn’t dispatch a syscall.Put a breakpoint in a 32-bit API function, and see where it leads:.This ends in an API call inside the 64-bit NTDLL, dispatching the syscall.Switching to 64-bit mode and modifying the function arguments to

ISLIDE INTO HEAVEN SERIES

Instead, it calls these new DLLs, and they start a series of calls and jumps,.

32-bit ntdll doesn’t dispatch syscalls or communicate directly with the.

Every WoW64 process contains a native version of NTDLL + a few newĭLLs (wow64.dll, wow64cpu.dll, wow64win.dll).

Subsystem exist inside the 64-bit process, communicating with the 64-bit

Native NTDLL and unique DLLs are used for compatibility, letting the WOW64.

Complete subsystem, including 32-bit main image, 32-bit DLLs, all living in the.

Windows on Windows64 – a 32-bit subsystem inside a 64-bit process.

We will also see how it is possible to exploit this mechanism in order to create smarter malware that evade Next-Generation and Previous-Generation AV products. In this talk we will dive into the WoW64 Subsystem and explain how a 32bit Application performs 64bit (native) system calls. The Operating System then relentlessly moves forward to the 32bit world by loading the WoW64 Subsystem, in order to let the 32bit Application execute freely. How the subsystem actually does this remains a question to many.Īny Application, whatever its type, begins its execution in 64bit mode. The Wow64 Subsystem supplies a natural environment for the legacy 32bit Application and enables anyone to run them on newer 64bit Operating Systems without any trouble. However, in practice Windows contains many secrets, and one of those secrets is the WoW64

The native 64bit environment cannot directly support the execution of a 32bit Application.ģ2bit Applications expect several surrounding pillars which help it perform necessary actions,Īnd those no longer exist in a 64bit environment. So how can a 64bit Operating System run a 32bit legacy Application? The old days of 32bit applications are long bygone, nowadays most Operating Systems are running in a 64bit environment, requiring 64bit applications.