Back in April, the largest known e-mail security breach took place when Epsilon, an online marketing corporation, had their clients’ lists of e-mail addresses stolen by sophisticated cyber thieves.

Epsilon was in charge of maintaining the e-mail databases and cam-paigns of some of the largest corporations in the country, including 1-800 Flowers, Best Buy, Walgreens, JPMorgan Chase, Capital One, and more. In fact, there’s a good chance that you’ve received multiple “apology” e-mails from these vendors.

While some said the breach didn’t cause a whole lot of damage, we dis-agree. Essentially, these cyber criminals now have the ability to invent highly sophisticated phishing attacks by creating e-mail offers that look like legitimate promotions coming from companies they (the people whose e-mail addresses were stolen) buy from and trust.

And though it’s already common for cyber thieves to impersonate credible organizations with what appears to be legitimate e-mail messages that seek to verify account information, this recent breach of security allows cyber thieves to be smarter and even more targeted with their scams.