The public v4.0 Pin cracker that works
https://gamesguru2.googlepages.com/home
Yeah, that one. He has the video on youtube using it, and gives that link. I've personally tested it, and it worked for an account I had hacked. Just put in the info it asks for, start the GGLess maple story client and let it do it's thing. When it's finished, it'll log you in and show you your PIN. Make sure to close the GGLess maple and open the regular version so that you can actually play.
Obviously I didn't make it, but it can be handy. I don't recommend using it for hacking other people's accounts, just for your own recovery <_<
By the way, given how it's public, it'll probably get detected really soon. Get it while it's hot <_<