Using the present perfect passive would normally suggest that the mugging has only just happened and the victim is still suffering the immediate effects. Someone calling the police straight after the crime is more likely to say "I've been mugged" rather than "I was mugged". However talking about something that happened five years ago "I was mugged in 2015" would be the probable choice

I agree with Bramwell's answer, especially because he used the word 'normally' in his answer. However, I think it's worth pointing out that we also use Present Perfect to talk about life experience when we don't want to specify the time that an event happened. So, in that case it doesn't really matter whether the event happened recently or not. Something like this is quite possible: Person A: I feel terrible, I've just been mugged. (When? recently connected to the present) Person B: I can imagine how you feel. I've also been mugged. (When? not specified, probably not recently - only the experience of being mugged is expressed)

Chrise, you have a very good answer from Bramwell.