Researchers have discovered an iPhone vulnerability that let hackers read and listen to encrypted messages, collect personal data, and take control of the devices.
But iPhone owners can protect themselves by following a simple step: Keeping their devices updated with the latest version of iOS.
Since the hack was found by Google researchers, Apple released a software update that is intended to fix the security hole.
To ensure that your phone is covered, users should check that their current iOS version is at least 12.4.1 by going to the device’s settings under “General.” That software update includes the necessary security upgrades to prevent iPhones from being compromised.
The hack affected iPhones using software from iOS 10 to the current iOS 12. The hackers would get iPhone users to go to compromised websites and then exploit a number of vulnerabilities in their devices.
The affected websites had thousands of visitors weekly, Wired reported.
The hackers could see live data location and messages, even those on encrypted messaging services like WhatsApp or Signal. They also had access to photos, contacts passwords, and other information. According to the release, the hackers were focused on stealing files and viewing live location data.
The hack is notable for the length of time it went undiscovered—two years— before a patch was released. It also stands out for targeting iPhones, which have a reputation for security.
Apple made its patch available in February, a week after the Google researchers alerted Apple about the problem. Google’s Project Zero team, which discovered the hack, revealed the security hole publicly this week.
Apple and Google did not respond to a request for comment from Fortune about the hack and how to protect against it.