Transcript for On the Trail of Target Cyber Thieves
christmas eve, new credit card worries as the investigation into the breach at target moves forward. Millions of customers effected and tonight are investigators getting any closer as to who is behind that. Abc's linzie janis on the case again tonight. Reporter: The man who broke the news of the massive target hacking my be zeroing in on the culprits. Cyber security expert brian krebs showed us this black market website, known as card dump, where he says criminals are selling stolen data from target customers right now. You can see how cards are advertised. By expiration date, the card holder's zip code, the issuing bank and the prices begin $26 and $45. Now krebs says he's traced the site to cyber criminals in the ukraine. He also says the people who stole the target data may have gotten ahead of themselves. So the bad guys are stealing so much of this information, they're having a hard time charging what they want for this information and they're having a hard time off loading it to people who -- enough people who want to buy it. Reporter: And tonight victims of the security breach are being hit again. This time, scam artists posing as target representatives sending sham messages to affected customers, hoping to steal more personal information. Target says it will post official communications on its websites to help customers identify authentic e-mails. They say their team is working with the secret service around the clock through christmas to get to the bottom of this. In the meantime if you get an e-mail claiming to be from target asking you to input your information, don't do it, it's probably a scam. David? Be very careful. Linzie janis, thanks for being here on christmas eve with us.
This transcript has been automatically generated and may not be 100% accurate.