Citigroup customers hacked

WASHINGTON (CNN) – Banking giant Citigroup announced Thursday that hackers breached security settings and stole information from customers.

Citigroup says someone accessed the personal information of about 200,000 American customers, but will not say how much money was lost. The company says it found the breach through routine monitoring and is contacting the customers impacted by it.

The hackers were not able to retrieve any personal information from the customers except account numbers, customers' names and contact information.

"With just your name and your contact information, what hackers can do is they can sell that information for identity fraud or identity theft," said cyber-security consultant Mark Rasch. "They can try to poach customers from Citibank, but more importantly, they can use that information to try trick Citibank tellers or other operators into believing that they're the actual customers."

Rasch, a former cyber-crime prosecutor with the Justice Department, believes the banks' built in protections only go so far.

"What we continue to see is an increase in folks actually targeting intellectual property that can lead to economic growth, and that's something that countries have become very much aware of," Rasch said.  "Hacking is at the forefront of that in an increasing sophisticated attack."

Rasch and other experts say the recent hackings of Citi, Lockheed-Martin, Sony Playstation and GMail are likely not related, but do have common threads.

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