Is it possible to write a PE exe program that will modify itself in memory and write this new version of itself to another exe, for example "prog2.exe"? how to do it? maybe using CreateFileMapping API?

Thanks!

yes, it possible

How?

http://www.security.org.sg/code/loadexe.html <--- might be helping...

OzzY, it's not possible to have this working for all windows versions.

The most reliable way, if you really must do this, is to have an external app write to your .exe file.

Maybe copy the program to a second .EXE file, and execute it with some command line option to write to the first .EXE?

Yes, that would work. It's clumsy, though.

Another method that "works okayish" would be to inject code to some other process... but that's even more of a kludge. Forget all about the "cute" tricks that unmap the process etc.

u can check example called 'selfsave' on my homepage
http://comrade.ownz.com/sources/selfsave.zip

Turbo GREP 5.5 Copyright (c) 1992, 1999 Inprise Corporation
Syntax: GREP [-rlcnvidzuwo] searchstring file[s] or @filelist
Options are one or more option characters preceded by "-", and optionally
followed by "+" (turn option on), or "-" (turn it off). The default is "+".
-r+ Regular expression search -l- File names only
...
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-u xxx Create a copy of grep named 'xxx' with current options set as ...
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