Hackers were able to remotely install surveillance software on phones and other devices using a major vulnerability in messaging app WhatsApp, it has been confirmed. WhatsApp, which is owned by Facebook, said the attack targeted a “select number” of users, and was orchestrated by “an advanced cyber actor”. A fix was rolled out on Friday. The attack was developed by Israeli security firm NSO Group, according to a report in the Financial Times. On Monday, WhatsApp urged all of its 1.5 billion users to update their apps as an added precaution.