The USB charging ports that have popped up at airports, coffee shops, and even outdoor stations around cities in recent years are definitely a lifesaver when your smartphone is down to its last bit of juice. A dead phone is annoying at best and downright dangerous at worst, so it’s totally understandable why you’d jump at the chance to revive it at your earliest opportunity.

However, those public ports might not be as benevolent as they seem. According to Afar, hackers can load malware onto those stations—or on the cables left plugged into the stations—which can then deliver passwords and other data right from your device to the hacker’s. If you have used a public port recently, don’t panic; TechCrunch reports that these cases are fairly rare. Having said that, it’s definitely better not to risk it, especially considering what a nightmare it would be to have your identity stolen.

The Los Angeles County District Attorney’s Office explains that the easiest way to prevent becoming a victim of this type of scam, often referred to as juice-jacking, is simply to abstain from using public USB charging ports. Instead, invest in a portable charger, or plug your own charger into an actual AC power outlet.

But unoccupied power outlets are notoriously hard to come by in public places, and portable chargers themselves can also run out of battery life. Luckily, there’s a small, inexpensive device called a data blocker that will enable you to use public USB charging ports without worrying about juice-jacking. It looks a little like a flash drive with an extra slot, but it lacks the two wires usually found in USB chargers that can download and upload data. That way, your device will charge without transferring any information.

You can get two of them for $11 from Amazon here.

[h/t Afar]

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