Starbucks cafe's wi-fi made computers mine crypto-currency

Starbucks has acknowledged that visitors to one of its branches were unwittingly recruited into a crypto-currency mining operation.
The wi-fi service provided by one of the coffee chain's Buenos Aires outlets surreptitiously hijacked connected computers to use their processing power to create digital cash.
Starbucks said that it had taken "swift action" to address the problem.
But one expert said it highlighted the risks of using public wi-fi.
It is not clear how long the malware involved was active or how many customers were affected.
The issue was identified only when the chief executive of a New York-based technology company logged into the service and noticed the problem.
Noah Dinkin was alerted to the issue by a delay he experienced before being able to start using the net, and posted his discovery to Twitter.
Although he initially believed the code had been designed to force his laptop to try to create bitcoins, other users noted that it had in fact been designed to mine another digital currency, Monero.
Mining involves solving complicated mathematical equations to verify crypto-currency transactions.

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