Used by more than 1.5 billion people around the world at least once a month and over one billion every day, WhatsApp is not always as “reliable” and “secure” as Facebook would like you to believe. Acquired by Mark Zuckerberg’s social media behemoth back in 2014, the instant messaging app vanished from Google’s Play Store at one point recently while security researchers discovered a number of scary vulnerabilities a few months prior to that mysterious (temporary) disappearance.

While said bug fix discreetly rolled out to the masses in mid-September as part of an update to app version number 2.19.58, many WhatsApp users could still be vulnerable to a sneak group chat attack by a “bad actor” looking to prevent you from opening the IM app for some reason. In order to avoid that, you simply need to make sure you have the latest version of WhatsApp installed on your Android handset or iPhone.

Once the malicious message hits the target group, there’s nothing left to do for victims of this incredibly efficient attack but uninstall and reinstall WhatsApp to regain access to the app, and perhaps worst of all, delete the group containing the mischievous text. Once again, all you have to do to dodge this scary threat is keep the app up to date, which you should really do even in the absence of revelations like these as smaller but sometimes similarly important security enhancements are frequently applied in new WhatsApp versions.