It hasn’t been completely verified yet, but a user named "muslix64" has posted an exploit in a thread on the Doom9 forum claiming that he has been able to circumvent AACS, the encoding format used to protect HD DVD content.

"Muslix64" claims to have completely backed up an HD DVD movie and provides a Rapidshare link to downloading BackupHDDVD, a small Java-based utility that aids users to backup their HD DVDs. A YouTube link to see the program in action has also been posted.

"Muslix64" describes the utility as "This is a java based command line utility that decrypt vide files (.evo) from a HD DVD disk that you own, to your hard drive and you can play them back with a HD DVD player software."

Although much of the dirty work in backing up a HD DVD movie is done by the tool, users are still required to find their own cryptographic keys for the disc being copied. No guidance is provided to help users find the keys, but the author suggests the process is trivial.

Although the exploit hasn’t been completely confirmed yet, if it turns out to be true it could mean a number of things. For one, it is possible that we might start seeing pirated HD DVD content. In addition, since Blu-ray also uses AACS, we might see a similar crack be released for Blu-ray movies in the next couple of weeks.

"Muslix64" claims the tool works on his XBOX 360 external HD DVD player, but that the software should not be limited to just one specific player.