Decompile exe?

[outlaw]

Hello im new in these forums. I were just wondering here that is it easy to decompile exe file?


Sorry if this was wrong section or if i did anything wrong.

[MXP]

Decompiling into machine code is easy but not always very useful. Decompiling into source code edges towards impossibility for C and C++ programs.

[outlaw]

Decompiling into machine code is easy but not always very useful. Decompiling into source code edges towards impossibility for C and C++ programs.

Okay, thanks for the reply.

I got another question:

Is it easy to modify some lines on the .exe? (Without decompiling everything).

[Gonbe]

Not sure what you mean with 'lines', but if you want to modify something like strings or variable names or some other stuff, often a HEX editor will do. For example if your code is like:
[syntax="cpp"]
#include <iostream>

int main()
{
std::cout << "hello world!\n";
return 0;
}
[/syntax]

And you compile it, you can open the executable file, with some hex editor and you will see something like this:

h t t p://img98.imageshack.us/img98/3189/hexeditorsr0.jpg

and you can simply replace the string that i highlighted there.
(not sure if you can 'insert' symbols, but you can make it longer than the original as long as there is room for it. (00's in HEX, and make sure you end your string with '0a' in HEX)

Another popular program to modify / analize programs with is "Ollydbg" (www . ollydbg . de) though that requires ASM knowledge so i can't help you with that..

-edit-
Still can't post images or URLs

[outlaw]

Not sure what you mean with 'lines', but if you want to modify something like strings or variable names or some other stuff, often a HEX editor will do. For example if your code is like:
[syntax="cpp"]
#include <iostream>

int main()
{
std::cout << "hello world!\n";
return 0;
}
[/syntax]

And you compile it, you can open the executable file, with some hex editor and you will see something like this:

h t t p://img98.imageshack.us/img98/3189/hexeditorsr0.jpg

and you can simply replace the string that i highlighted there.
(not sure if you can 'insert' symbols, but you can make it longer than the original as long as there is room for it. (00's in HEX, and make sure you end your string with '0a' in HEX)

Another popular program to modify / analize programs with is "Ollydbg" (www . ollydbg . de) though that requires ASM knowledge so i can't help you with that..

-edit-
Still can't post images or URLs

Thanks for the reply, i think its too advanched for me to edit the .exe. :S

[ventsyv]

It is too advanced for most people. ASM knowledge is helpful somewhat but modifying decompiled exes is still extremely difficult.