Fox-IT Completes the Picture On the Factored RSA-512 Keys

An anonymous reader sends in this excerpt from the Fox-IT blog: "During recent weeks we have observed several interesting publications which have a direct relation to an investigation we worked on recently. On one hand there was a Certificate Authority being revoked by Mozilla, Microsoft and Google (Chrome), on the other hand there was the disclosure of a malware attack by Mikko Hypponen (FSecure) using a government issued certificate signed by the same Certificate Authority. That case, however, is not self-contained, and a whole range of malicious software had been signed with valid certificates. The malicious software involved was used in targeted attacks focused on governments, political organizations and the defense industry. The big question is, of course, what happened, and how did the attackers obtain access to these certificates? We will explain here in detail how the attackers have used known techniques to bypass the Microsoft Windows code signing security model."

Re:Short answer

[FrankSchwab]

I agree with you, Kjella.

The 48 MHz, ARM-7-like processor in our ASIC can do an RSA-2048 operation in 3-4 seconds. The 3000 MHz, 64-bit, OOE, multi-issue, TLA-up-the-Wazoo processor in the average $400 laptop should be able to do it in 3-4 milliseconds (http://www.cryptopp.com/benchmarks.html).

There is no reason not to be using RSA-2048 on the desktop. On a Webserver getting hit by millions, the 6-8x increase in CPU times is going to start getting noticeable. /frank