The Better Business Bureau and other experts today offered more warnings that a new round of spear phishing attacks could soon arise from the recent email data thefts from Epsilon.

"If you are a customer of one of the companies that had email data stolen, the [Better Business Bureau] is warning you to be on the lookout for phishing emails," the BBB said in a statement today.

Spear phishing emails are social engineering attacks that attempt to extract passwords or other data from specific individuals within a company or organization -- usually those who are likely to have access to sensitive or privileged information. In other exploits, sometimes called "whaling," the phisher attempts to extort money or data from an individual who holds a high-salary title in the organization.

Following this week's revelation of a major breach of email data from more than 50 companies via Epsilon, experts expect that the perpetrators could soon begin spear phishing the customer bases of the victim companies.

"Although consumers need to be especially careful in the next few weeks, our larger concern is a month or two down the road, when the story is not top of mind," says Matt Bitonti, COO of identity theft service provider iSekurity. "Identity thieves can strike at any time."

As if to illustrate the spear phishing threat, New York publisher Conde Nast this week revealed it was taken for some $8 million by a spear phishing attack. According to news reports, Conde Nast filed a lawsuit against a fraudster that sent emails posing as the publisher's regular printer and requesting payment to a new address.

Conde Nast and its printing company discovered the scam in time, and the $8 million payment has been frozen in the recipient's account, according to the news reports. The publisher is attempting to recover the funds.

"Once an attacker has someone's email address, name, and the place they do business with, they can perform spear phishing attacks," notes Nichola Percoco, senior vice president and head of the SpiderLabs research unit at security vendor Trustwave.

"The attacker crafts a message specifically tailored toward the recipient to obtain a higher likelihood of success," Percoco explains. "The payload of the attack might also be more damaging. Rather than just trying to get the end user to supply information to the attacker, the user might be prompted to click on a link that will deploy malware to their system."

Steve Dispensa, CTO and co-founder of authentication technology vendor PhoneFactor, agrees. "Phishing emails that appear to come from a person’s bank or a retailer they regularly receive emails from are more likely to be acted upon [after the Epsilon breach]," he says. "Unfortunately, it is very difficult for the average person to distinguish between a dangerous and a safe email. The result is likely an increase in the number of successful phishing attacks over the next few months."

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