And next tonight, a travel alert about summer vacation. A big resource on the road for anyone is free wifi, making it easy for you to go online. But tonight, we're learning that free offer can be a... See More
And next tonight, a travel alert about summer vacation. A big resource on the road for anyone is free wifi, making it easy for you to go online. But tonight, we're learning that free offer can be a kind of trap with thieves waiting. ABC's linsey Davis shows us how. Reporter: It's summertime. You're on the move, but trying to stay connected. Logging onto free wifi in hotels, restaurants and airports. But what you might not know is that if you logon to that free wifi, you could be rolling the dice with your privacy. Currently we have 260 networks and we traveled, what, one yard? Reporter: We're cruising the streets of New York, scanning for wifi hot spots. There's somebody's mobile wireless access. Reporter: Many of those wireless networks are unprotected. I can see everything they're doing. I would see their instant message conversations, the photos they're sharing. Reporter: Chester tells us many people are hacked while accessing free wifi. Now, when we talk about a coffee shop or a computer store, that offers free wifi, a hotel, even, is it safe for me to go on there? It's very easy for an intruder to see pretty much everything you're doing. That means if you're banking online, paying bills, a hacker could see that, too. I mean, free is nice, but you are paying with your privacy. Reporter: Chester says hackers even set up fake wifi spots to nap you. iPhone -- Reporter: In a matter of moments, he sets up a free network. In less than five minutes -- Got three androids and two iPhones and an iPad. Reporter: Users are logging in. When criminals do this, they pretend to be famous coffee shop names. Reporter: So there's nothing stopping us from going into a Starbucks, setting up free wifi that says Starbucks free wifi? Nothing. Reporter: Of course, Chester didn't peek on those who jumped on his open network, but someone with bad intentions could. Something to think about if you're tempted to save money of those data roaming charges by using free wifi. I don't think people understand the risk. I think they don't know. Reporter: I didn't know. Exactly. Reporter: So, here's what you can do. Use your cell phone data plan instead of free wifi. It may cost you in the short-term, but it is so much safer. Or consider paying a small monthly fee for a vpn, which encorrupting your anything information. If you don't have that, always assume wifi connections are being eavesdropped on. Big surprise for everyone here today. Reporter: Yes. Thank you so much.
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