Source: http://gizmodo.com/5640907/hdcp-master-key-is-real-but-it-wont-do-you-much-good
CNET talked to all types of security folk to get the scoop on the implications of the leaked key, and while Cryptography Research president Paul Kocher says it'll let you "play god for this protocol,"—designed to protect content as it's beamed from set top boxes and Blu-ray players to HDTVs over HDMI—what the key really means is that a few years down the line there could be some hardware boxes that'll be able to create perfect bit for bit digital copies of HDCP-protected movies and broadcasts.
HDCP, short for High-bandwidth Digital Content Protection, is built directly into the chips in TVs and Blu-ray players, an Intel spokesperson explained, and to reap the benefits of the key you'd have to "implement them in silicon...a difficult and costly thing to do." Of course, Intel's still pushing ahead with the technology, which they license to all sorts of hardware manufacturers, so it's in their best interest to downplay the significance of the key making it into the wild.
But for those up to speed in the cryptology world, the appearance of the key is of little surprise. In 2001, researchers at Carnegie Mellon determined that only 39 HDCP-equipped devices would be required to reverse engineer the master key. So it's been something of an inevitability that someone would figure out the "master key"—the idea of a "master key" in any context is pretty enticing—but for now there will still be far easier ways for media pirates to do their pirating. [CNET]