BROOKLYN - Grinch-like hackers can literally steal Christmas through something as small as a cellphone.

Security researchers with Trustwave show that by swiping your credit card on a smartphone--which many retailers do--software used to process the payment can take your personal information. The software may not encrypt that information right away, leaving it open in the system.

Then, hackers can manipulate the device in a way that allows them to track activity, like credit card numbers swiped or typed in.

Trustwave recommends that retailers test their security and break the system before it is deployed to find the weak points.

They also recommend customers always keep tabs on transactions, especially during one of the busiest shopping periods of the year.