Credit card thieves are now making donations to charities - in your name. It's the newest tactic to ensure thieves get the best price for personal data they sell on the black market, according to Symantec, a security firm.

Like reputable online retailers that check you have enough in the bank by making a small deposit, before OKing an order for an expensive laptop, thieves are now making small donations to ensure the card they just bought is valid.

"Even the bad guys want to verify the other bad guys," Javier Santoyo, Symantec's manager of security software, said in a Friday blog post. A verified credit card can sell for up to $18, compared to $6 for credit card information not checked.

The assumption by the bad guys is that credit card fraud monitoring services won't notice a small donation to the Red Cross as easily as a $2,000 charge to some Eastern Europe online store.

Symantec advises consumers inspect their credit card statements for even small charges that seem out of place.