Hi there.
I am really busy in these days i can't use this forum like before but i'll be back soon.

Well, i am learning c programming at Harvard unversity cs50 course. After some weeks I've developed some ciphers and ...

Now i know the basics about c. So please let me know if there is any books out there about writing exploits only with c that i can study after this course?

Thank you so much

Thanks kojiman. Is it good for beginner like me?

Hey, take a look at the "Open Security Training" courses, esp. "Into to Software Exploits" by Corey K., thats a good place to start.

http://opensecuritytraining.info/IntroductionToSoftwareExploits.html

Man thanks for your answer but i am busy in these days i don't have enough time to learn a super hard programming language called assembly!!!!! but thanks again maybe i'll go for it later.

Open Security Training is like gold given for free but sadly the videos are wayyy tooo gigantic and the classes are in Assembly.

You're going to need to learn it then. Just because an exploit is written in C, Python, Perl, Ruby, etc., doesn't mean that assembly isn't involved. More often than not, those are just the deliver mechanism for the exploit. You're going to have to get comfortable working in a debugger and understanding assembly. There's no way around it.

An exploits has two parts: there is a dropper/delivery program that can be written in C, Python, etc.  That is not complicated to write.  The real trick is finding the vulnerability, figuring out how to exploit it and developing the shell code.  You won't be able to do much without learning some assembly.  Without it, you can't customize shell code, debug using gdb/IDA/Olly, or use any non-trivial exploitation technique (e.g. return-into-libc). 

But don't despair Cyber.spirit, you really don't need to be an assembly guru in order to write exploits. I would say you only need limited knowledge to get you started.

Start with http://www.securitytube.net/groups?operation=view&groupId=6 then http://www.securitytube.net/groups?operation=view&groupId=5 and you will know more than what you need to write exploits.

What you really need is understand how operating systems work and learning a bit of assembly will help you a lot in understanding the registries, the stack, etc. And again, you really don't need to be good at assembly. Just write a few programs and you will be fine.

For the rest C, python, ruby, perl, etc are, like ajohnson said, only there to help you deliver your shellcode.

Good luck and post your questions!