Apple’s latest iOS software update remedies an iPhone code glitch that was clogging up 911 lines with bogus calls across the country.

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Hacker’s 911 iOS exploit clogged phone lines

As if 911 operators didn’t already have enough to deal with, they were being hit with a massive influx of fake calls beginning October 2016 that resulted from a bug in iOS software.

The problem was an 18-year-old hacker in Arizona allegedly found a glitch in the code that caused iPhones to repeatedly dial 911. The hack worked because iPhone software previously allowed users to initiate a call by clicking just once on a phone number.

Things really picked up when the hacker shared the exploit on Twitter and teenagers around the nation began prank calling 911 en masse.

Operators in at least a dozen states were overwhelmed by thousands of prank calls, according to The Wall Street Journal.

Apple released an update this week that shores up the vulnerability across all apps. As a result, users will now always have to press a second confirmation before a call can go through.

911 operators face network problems that foul up calls

This isn’t the first problem 911 has seen with legitimate calls getting through in recent weeks.

In early March, a 6-month-old infant died after his babysitter was unable to reach 911 operators. That event took place in Dallas at a time when the city was experiencing an ongoing problem with 911 calls getting through on T-Mobile’s network.

And days before that happened, AT&T had a service outage that prevented mobile callers in Florida, Tennessee, Texas and other states from reaching 911 emergency service.

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