The hacker posted details of his exploits late last week on the Internet in several places, and at least one third party has confirmed the methodology.
AACS was developed by Microsoft, Disney, Sony and others to protect the content of high definition (HD) DVDs, including Toshiba's HD-DVD and Sony's Blu-ray systems.
According to the Reuters newswire, Muslix4 has posted technical notes and videos, together with the encryption codes showing how to copy several films, including Warner Bros' Full Metal Jacket and Universal Studios' Van Helsing.
The hacker has also promised to post more source code later today that will allow users to copy a wider range of titles.
As you might guess, the reports have sent the HD-DVD companies and their allies into PR meltdown mode, and the movie companies are not far behind.
Has Muslix64 really cracked ACCS? Depends on which you look at the issue, say my seriously tech pals.
The fact that you need the source code for each specific movie doesn't make it the most flexible crack in history, but as a first step, it's pretty astonishing...