Ferguson has been critical of many people involved in football in his much-publicised book - including Benitez and Liverpool captain Steven Gerrard - but the Napoli boss has refused to be drawn on the matter.
The 53-year-old told The Independent: "The problem with answering on those comments about me - or about Steven Gerrard - is that it only adds to the publicity.
"All I can say is that at the time, we were doing our best to defend our team and our club. We got a reaction. We did a good job. We were challenging well.
"They were good times for the club. We can let the things that we did at Liverpool and the success we had make our answer for us. Beyond that, there is nothing more that I think I can say."
Benitez has guided his current club Napoli to second place in Serie A this season.