Apple Computer, Inc. today said it has closed the backdoor hack in its iTunes online music store, which allowed hackers to download DRM-free music.

The company fixed the security vulnerability and said users with iTunes 4.7 will be able to download music from its library. According to the company, about 15 percent of the buyers will have to update their iTunes software.

Out of the three hackers included DVD Jon, who is notoriously famous for his hacking techniques.