The Secret Service has confirmed what you've probably suspected for a long time: Public computers at hotels are ridiculously insecure, and you're taking a gamble with your personal data each time you use one.

Security expert Brian Krebs shared a private Secret Service bulletin directed toward the hotel industry. The American government warns hotel managers that public computers in their establishments are, by and large, vulnerable to simplistic attacks that can compromise some of their patrons' most sensitive details.

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Hotel computers are obscenely easy for hackers to get ahold of, considering that attackers can have more-or-less unrestricted physical access to public computers (many hotels have a "business center," where visitors can browse the Internet, check e-mail and print documents) for the cost of a single night's stay.

Hacking computers remotely takes a little know-how, but compromising physical computers is usually as simple as installing a surreptitious keylogger via a USB stick. Keyloggers are what they sound like: They keep track of everything that users type into a computer, then transmit this information back to the malefactor.

Given that users at hotels use public computers to check email, print boarding passes, pay for travel arrangements and download private business information, it's not too hard to imagine what an imaginative hacker could do with this information. Worse still, there isn't much that even a savvy hotel operator can do to prevent this misuse.

As usual, users will have to take responsibility for their own safety when it comes to hotel computers. Using your own computer or mobile device is much more secure than using a hotel machine, so bring a device and use hotel Wi-Fi or mobile data when possible. If you need to print documents, it's probably safer to save them on a mobile device or USB stick and transfer them to the hotel machine.

Not every hotel is compromised, of course; the Secret Service did not provide estimates on how prevalent hacking hotel machines was, just that it happens and that it's very easy to do. Still, a little caution is probably wise; nothing ruins a vacation quite like having your identity stolen.