Abstract
We cryptanalyze a recently proposed matrix-based MOR cryptosystem. The security of the system depends on the difficulty of solving the following discrete logarithm problem: given an inner automorphism φ of SL(d, 𝔽 q ) and φ a (each given in terms of their images on generators of SL(d, 𝔽 q )), find a. We show that this problem can be reduced to a small number of similar problems in quotients of polynomial rings and solved in subexponential-time.
Notes
Communicated by M. Kambites.