The present invention relates to a security control comprising a first controller having a first clock generator for generating a first clock signal, a separate second controller having a second clock generator for generating a second clock signal, wherein the first clock signal is output to a first input of the first controller and to a first input of the second controller, and the second clock signal is output to a second input of the first controller and to a second input of the second controller. In addition, the present invention relates to a method for operating a security control.