Microsemi Rejects Researchers Claim of Backdoor in its Chips

Researchers who claim that ProASIC3 chips have a built-in backdoor respond to Microsemi
By Lucian Constantin
News Jun 2nd 2012

Semiconductor company Microsemi has issued a statement denying that one of its products, a popular silicon chip called ProASIC3, has a backdoor built into it.

The ProASIC3 field-programmable gate array (FPGA) -- a chip designed to be configured and programmed by customers according to their needs -- has no designed feature that would enable circumvention of the user security, Microsemi said Thursday in a message on its website.

ProASIC3 chips are integrated into systems used in many industries, including the military, for various applications. The chip is marketed by Microsemi as having one of the highest levels of design security on the market.

University of Cambridge Ph.D. candidate Sergei Skorobogatov and Christopher Woods, a hardware security researcher at U.K.-based research company Quo Vadis Labs (QVL), claimed that they discovered an undocumented function in the ProASIC3 FPGA that can be used by an attacker with physical access to the chip to extract the intellectual property (IP) stored on it, despite such information being encrypted with a user-defined 128-bit AES key.

Skorobogatov and Woods were planning to release in September at the Cryptographic Hardware and Embedded System workshop a research paper that explains how they found the backdoor. However, a draft version of their paper leaked online and was used as a source for news stories earlier this week.

In the draft version, the researchers explain that they used a technique called Pipeline Emission Analysis (PEA), patented by QVL, to significantly increase the efficiency of differential power analysis (DPA) methods.

DPA attacks can be used to extract cryptographic keys from hardware devices by analyzing fluctuations in their power consumption during normal operation. However, traditional DPA methods are not very accurate and usually require a lot of time and expensive equipment to use successfully.