Comments on the security of fast encryption algorithm for multimedia (FEA-M)

We show that the Fast Encryption Algorithm for Multimedia (FEA-M) proposed by Yi et al. (IEEE Trans. Consumer Electronics, vol.47, no.1, p.101-7, 2001) is insecure. In particular, we present a simple attack that reduces the complexity of obtaining both the session key and the master key to solving a set of linear equations. The low complexity of the attack combined with its simplicity makes it feasible in many multimedia applications.