  This paper investigates hardware cyber-security risks associated with channel
decoders, which are commonly acquired as a black box in semiconductor industry.
It is shown that channel decoders are potentially attractive targets for
hardware cyber-security attacks and can be easily embedded with malicious
blocks. Several attack scenarios are considered in this work and suitable
methods for mitigating the risks are proposed. These methods are based on
randomizing the inputs of the channel decoder to obstruct the communications
between attackers and the malicious blocks, ideally without changing the
decoding performance.
