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Massive Data Breach Leaks Customer Names, Email Addresses

hand on keyboardA cyber-attack on an online marketing firm has impacted a wide array of companies and customers in what could be the largest data breach in U.S. history.

The online marketer, Epsilon, sends out more than 40 billion email ads and offers each year, typically to users who register with a company's website, or give their email addresses while shopping online. On Friday, Epsilon announced that a hacker had gained access to its clients' customer files, which contain personal information on individual consumers.

Many of Epsilon's clients, including Citigroup, Capital One, and JP Morgan, have already issued warnings to their customers, informing them that their email addresses and, in some cases, their first names may have been leaked. The College Board, which administers the SAT and represents over 5,900 colleges, also appears to have been affected. Fortunately, the attack doesn't seem to have jeopardized consumers' credit card numbers, social security numbers or passwords.

Police are investigating the breach, though it remains unclear how many consumers could be affected. "While we are cooperating with authorities and doing a thorough investigation, we cannot say anything else," said Epsilon spokeswoman Jessica Simon. "We can't confirm any impacted or non-impacted clients, or provide a list (of companies) at this point in time."

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