Swampjack virus

the long version

In a joint venture between the United States and Great Britain, the CIA and SIS have been covertly developing a highly sophisticated new cyber weapon. But then Peter Chapley, a key CIA operative working within SIS, mysteriously disappears in a London underground station while in possession of the prototype weapon. The Head of Weapons Intelligence at the CIA calls on Peter's own brother, retired agent Roger Chapley, for help. Roger's straightforward final assignment is to track down Peter in London and recover the weapon before it falls into enemy hands. The complicated part of the mission is determining whom to trust and what is fact from fiction, and whether or not his brother has turned traitor!"--Back cover.