Did you try maybe googling it first? Ugh. No. If bitcoins are hackable then everyone on earth is fucked because banking uses the same encryption SHA256. Don't worry about it. A much more likely way to lose your bitcoins would be someone hacking your computer, stealing a paper wallet or robbing you at gunpoint.
Actually, I want to know how to attack the bitcoin address.
Get an address with a high amount of bitcoin in it. How can a hacker attack this address? There is no other information. There's only address information and bitcoin amount.
This is actually very easy.
1) buy a pretty good quality computer. Best if fully dedicated and separate from your normal computer.
2) download and install Vanitygen
3) 64 vanitygen64 (64 is faster and works better than normal vanitygen)
4) start scan on the address like this at the command line: vanitygen64 1FuckYouc6zrtHbnqcHdhrSVhcxgpJgfds
It will take some time for sure. But soon you will have the key for that address.
Don't let the morons around here tell you it is impossible. That is just plain wrong. It is scientifically provable that this works. Dumbasses who don't understand statistics love declaring this impossible. Vanitygen guesses millions of times per second. With enough seconds, it is not impossible.
It would be much faster to buy a gun, a plane ticket and a body bag. But let tell your great great great great great(^256) grandkids to report back once they hacked my bitcoin address.