How to hide debugger?

[deXep]

Hi my nice guys!

I'm working on a dumper and I cannot grab FS base via
GetThreadSelectorEntry
it returns TRUE but LDT_ENTRY is still NULL.

and I tried use address of debugger becoz all PEB is in the same address
this code works well
mov eax, fs:[30h]
inc eax
inc eax
call write_mem
but if I code like these:
mov edi, fsbase; grabbed
lea eax, [edi+30h]
call read_mem
then ReadProcessMemory return 0, last Error is PARTIALLY_COPY

I'm mad for such a strange problem

regards

well fs is not same on all platforms (especially in xp-sp2 fs segment is mapped to random addres (it used to be constant uptill w2k -sp4 i think viz 0x7fffd000 )

you need to fetch the fs via a different mechanism viz
ZwQueryInformationProcess() basic info class struct and look for *ppeb in there

take a look here on a sample implementation

http://www.openrce.org/blog/view/44

[deXep]

Thx JuneMouse, nice stuff!

[NeOXOeN]

Nice Post JuneMouse ..very usefull


bye NeO