International audienceThe miniaturization issues from the advanced integrated circuit manufacturing technologies lead to increase the probabilities of single node upset and multiple upsets errors of neighbor nodes. The study of such conjecture is mandatory to specify the protection requirements. This paper deals with the study of such single and multiple errors due to the impact of a single particle in the control unit of complex devices such as processors. Because the layout of the studied device cannot be anticipated, the node’s neighborhood is thus unknown. To deal with this issue, this work presents the results of both exhaustive and random fault-injection experiments performed at register transfer level (RTL) and targeting the control bits of LEON3 processor. Fault injection is achieved by means an automatic netlist fault injection tool called NETFI-2