How a Crypto ‘Backdoor’ Pitted the Tech World Against the NSA24/09/2013 22:41
Source: Threat Level
In August 2007, a young programmer in Microsoft’s Windows security group stood up to give a five-minute turbo talk at the annual Crypto conference in Santa Barbara.
It was a Tuesday evening, part of the conference’s traditional rump session, when a hodge-podge of short talks are presented outside of the conference’s main lineup. To draw attendees away from the wine and beer that competed for their attention at that hour, presenters sometimes tried to sex up their talks with provocative titles like “Does Bob Go to Prison?” or “How to Steal Cars – A Practical Attack on KeeLoq” or “The Only Rump Session Talk With Pamela Anderson.”
Dan Shumow and his Microsoft colleague Niels Ferguson titled theirs, provocatively, “On the Possibility of a Back Door in the NIST SP800-90 Dual Ec Prng.” It was a title only a crypto geek would love or get.
The talk was only nine slides long (.pdf). But those nine slides were potentially dynamite. They laid out a case showing that a new encryption standard, given a stamp of approval by the U.S. government, possessed a glaring weakness that made an algorithm in it susceptible to cracking. But the weakness they described wasn’t just an average vulnerability, it had the kind of properties one would want if one were intentionally inserting a backdoor to make the algorithm susceptible to cracking by design.
For such a dramatic presentation — by mathematicians’ standards — the reaction to it was surprisingly muted. “I think folks thought, ‘Well that’s interesting,’ and, ‘Wow, it looks like maybe there was a flaw in the design,’” says a senior Microsoft manager who was at the talk. “But there wasn’t a huge reaction.”