Cryptographer claims break in Intel video encryption
- 16 August, 2001 10:39
A Dutch cryptographer claims he has found a way to crack technology developed by Intel that protects digital video from pirates. However, he said he won't publish his findings because he is afraid he will be prosecuted or sued in the US under the 1998 Digital Millennium Copyright Act (DMCA).
"Intel's HDCP (High-bandwidth Digital Content Protection) is fatally flawed. An experienced IT person can recover the HDCP master key in about two weeks," said Niels Ferguson, in an interview.
Ferguson, a noted cryptographer who works as an independent cryptography consultant, first talked about his findings Sunday at the Hackers at Large 2001 (HAL) conference in Enschede, Netherlands. Ferguson has worked for, among others, the National Research Institute for Mathematics and Computer Science in the Netherlands.
The master key can be used to decrypt HDCP video content, to impersonate a device and to build new devices that will work with the official HDCP devices, according to Ferguson. To get the master key, an expert would need to have four computers and 50 DHCP panels running for about two weeks, he said.
"If this master key is ever published, HDCP will provide no protection whatsoever. The flaws in HDCP are not hard to find," he said, noting that it is impossible to find the key now because digital monitors using the HDCP technology aren't available yet.
Intel presented HDCP in February 2000. The technology is designed to encode digital video on the DVI (Digital Visual Interface) bus, which is expected to be in devices such as DVD (Digital Versatile Disk) players, PC monitors, TVs and digital video cameras next year. DVI is touted as the successor to the VGA (Video Graphics Array) display systems.
Ferguson said that although he usually publishes his findings, he won't disclose the weaknesses in HDCP. A lawyer with the Electronic Frontier Foundation (EFF) told him that he risks being prosecuted or sued under the DMCA, a controversial law that makes it a crime to circumvent copyright protection mechanisms built into software and devices.
Ferguson, who travels to the US frequently, is frustrated by the DMCA and scared because of the arrest of Russian programmer Dmitry Sklyarov in July and by threats made by the music industry against Princeton University Professor Edward Felten.
"I would love to send my article to Intel, but don't know what the legal consequences would be. Intel has been very friendly," said Ferguson, who acknowledges that others have found flaws in HDCP, but claims he is the first to have discovered a "complete attack" -- a way to find the master key to HDCP.
Representatives at Intel were not available to comment.
Felten will finally present a research paper on how to crack digital music encryption Wednesday at a conference in Washington D.C. The paper was previously withdrawn from another conference in April after the Secure Digital Music Initiative (SDMI) and the Recording Industry Association of America (RIAA) claimed that presenting the findings would be in violation of the DMCA.
Felten and his team have filed suit against the SDMI, the RIAA, the US Department of Justice (DOJ), and a company that made one of the watermarks Felten's team cracked, requesting First Amendment protection to present the research without fear of reprisal.
"The best solution to my dilemma would be for the judge in Felten's case to rule that the DMCA is unconstitutional," Ferguson said.
Ferguson explains his position at www.macfergus.com/niels/index.html.