Downing Street computer systems are suspected to have been infected by powerful hacking spyware linked to spies in the United Arab Emirates.
It led to Boris Johnson’s mobile phone being analysed by cybercrime investigators and, although the sweep of devices failed to identify the source, has thrust the software used into the spotlight.
So just what is Pegasus, how does it work and who can be targeted?
One expert warned that it effectively means ‘every phone in every pocket is