We’ve written before about how computer security is
something of an arms race.
You defend, and then the crooks figure out what you’re looking for and therefore how to bypass or to trick your defences.
You figure out what they’re looking for and therefore how to outwit their latest tricks.
And so it goes on.
Although most malware samples these days aren’t strictly
computer viruses (a special class of threat that spreads by itself), blocking software from the Good Guys is still commonly referred to as an
anti-virus.
A counterattack by the Bad Guys that aims to trick an anti-virus is therefore jocularly known as a
anti-anti-virus.