IACR News item: 29 May 2015
Brice Minaud, Patrick Derbez, Pierre-Alain Fouque, Pierre Karpman
ePrint ReportAs our main contribution, we propose a new algebraic key-recovery attack able to break at once the secret-key scheme as well as the remaining public-key scheme, in time complexity 2^63 and 2^39 respectively (the security parameter is 128 bits in both cases).
Furthermore, we present a second attack of independent interest on the same public-key scheme, which heuristically reduces the problem of breaking the scheme to an LPN instance with tractable parameters. This allows key recovery in time complexity 2^56.
Finally, as a side result, we outline a very efficient heuristic attack on the white-box scheme, which breaks instances claiming 64 bits of security under one minute on a desktop computer.
Additional news items may be found on the IACR news page.