With over 1.5 billion users, any hack on WhatsApp is a concerning one, particularly when WhatsApp (and Facebook who own WhatsApp) shout from the rooftops about privacy and security.
It has been announced today (14th May 2019) that WhatsApp are urging all users to update their app due to a security bug (being reported as spyware) which allows hackers to take over your phone. The likelihood that you are infected is very small; the spyware is installed by calling you on WhatsApp and, even if the call wasn’t picked up, the spyware can be installed. So if you haven’t received or missed a call on your WhatsApp it is doubtful you have been infected, but better safe than sorry.
Remember that security patches on all your devices are really important. Try to get into the habit of updating all your devices regularly; I do mine weekly. It’s a bit of a pain doing them all but realistically only takes 10 minutes.