WASHINGTON – Public charging stations are popping up in shopping malls, tourist sites and other places. They provide free battery charges for smartphones, but security experts warn there is a risk.

The New York Daily News reports that hackers could take control of smartphones through public chargers.

Apple or Android smartphones could be vulnerable, though there have been no reports of it happening among any recently installed charging stations. The company that designs some of the charging stations says it would be difficult to co-opt the stations.

However, Billy Lau, a research scientist at Georgia Institute of Technology and a participant in last month’s Black Hat hackers’ convention in Las Vegas says he would never plug his phone into a public charger.

At the convention Lau demonstrated how a tiny computer that costs less than $50 to assemble could be used on public chargers to infect smartphones.

Alicia diVittorio, a consumer safety advocate at Lookout, a mobile security company, said she agrees there is a risk to public charging stations.

“We recommend against using them,” she says.

Computer security experts say such a tiny computer riding piggy-back on a public charger station could be used to steal bank information, email passwords and text messages. And a user wouldn’t even know the phone is infected.

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