CHICAGO (WBBM) — Experts say it might be the biggest computer breach in history. A company that provides e-mail advertising and communication services for banks and many other businesses has been hacked.

The companies affected include Best Buy, Chase, Citigroup, Capitol One, Walgreens, the College Board, TiVo, the Home Shopping Network, Verizon and Kraft Foods, among others.

LISTEN: Newsradio 780’s Mike Krauser Reports

If you do business with any of those companies, the hacker could have your e-mail address. Customers of Chase and Best Buy, for example, received an e-mail notification about the breach.

The company that was the target of the hacker is called Epsilon, a company that sends out 40 billion emails a year for its clients.

The company says your credit card information is safe. The hackers didn’t get that.

Consumer advocates warn if you get e-mails that seem legit don’t reply with personal information like social security or credit card numbers.

One business ethics expert, St. Xavier University Prof. William Kresse, says most people will recognize a “phishing” scam. But a small percentage won’t and will be handing over “the keys to the vault” to scam artists.

Steve Bernas, president of the Chicago Better Business Bureau, is also alarmed over the breach.

“We’ve already seen scammers taking advantage of the situation on the East Coast. We expect it will be moving here shortly,” he told CBS 2’s Mike Parker.

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