Researchers Decrypt HDCP Streams with FPGA Development Board

Last fall, Intel found that the master key for its HDCP digital copy protection scheme had been leaked to the Internet, and while the company claimed that it’d require too much effort and money to make proper use of it, it still made it clear that it’d be ready to take legal action against anyone who made use of it. For some people, a threat like that is the best possible challenge one could ask for, and leave it to researchers at Ruhr University in Germany for taking that challenge head-on.

Equipped with an FPGA board – a programmable integrated circuit – the researchers devised a man-in-the-middle attack that manages to decrypt HDCP content as it’s being fed from a Blu-ray played to a television. It seems that this is accomplished simply by programming the IC with the master key, and allowing the content to be fed through it before it reaches the TV.

The implications for this are rather minor, however. While such an implementation would allow you to rip a video stream as it plays, the most common use for HDCP has been with Blu-ray video, and if you already have the disc right in front of you, it would be much easier to just rip the disc to your PC and encode it there. After all, Blu-ray readers now retail for under $40, and as we proved last year, ripping a Blu-ray and encoding it can be done with totally free software.

At the same time, the FPGA board used for this testing retails for $349, so its cost is rather prohibitive given the little benefit this implementation actually offers. However, Intel stated that it’d be too intensive to make use of its master key, but the German researchers showed that it can in fact be done for relatively cheap. HDCP is just one form of copy protection that could likely be intercepted like this, so once a master key for digital content protection is leaked, it’s pretty-well game over.