'Most Dangerous' -- Spear Phishing

Ed Skoudis calls spear phishing "an oldie-but-goodie attack," but I can't figure out what's good about it. Spear phishing is a highly targeted e-mail with either an appended malicious attachment or a dangerous Web site link to client-side exploits. Strangely, the attack was birthed in the most inauspicious of ways; clumsy grammar and preposterous scenarios. How's that for irony? Imagine some e-mail, laden with broken English, lands in your inbox from halfway across the world detailing a half-baked scenario. And, what do we do? We click. I've done it. You've probably done it. We all regret it. (You won't regret the link).

Today's spear phishing attacks have taken on a new significance. They are becoming increasingly sophisticated, tailored, professional, personal and prevalent. It's a dangerous mixture, which is why Skoudis, founder and senior security consultant with InGuardians, makes it a point to include the attack vector on his important "Most Dangerous Attack Vectors" list.

"The messages are finely tuned to dodge antivirus and antispam now," Skoudis says. "This attack is still just as vicious and lethal via traditional e-mail."

The attack starts with the makings of any successful endeavor - research. "The company's own Web site is a treasure trove of information," Skoudis notes. Also, Securities and Exchange Commission filings contain useful personal and professional information on corporate executives. From here attackers can start to piece together a strategy, one conjured from legitimate reconnaissance. The e-mail goes out carefully crafted, grammar flawless. The attacks are directed toward executives and CEOs, but we're all vulnerable. It's becoming increasingly difficult to rely on our self filters to identify these attacks. Similarly, because spear phishing attacks no longer rely on mass e-mails or malicious code attachments, antispam and antivirus can't really deal with it.

One promising defense is Web application proxies that can look for malware flowing through them as browsers surf the net. Skoudis warns they aren't perfect though, and that there is a "performance hit from them based on their inspection of data."

"Plus, if the connection is encrypted via HTTPS, the proxy cannot inspect it unless it has the crypto keys to communicate with all the browsers," Skoudis adds. "Many organizations don't want to take that hit on deployment costs and complexity, so proxies' blindness to encrypted connections is a big issue." Here are some other ways to help protect yourself.

Have you been a victim of spear phishing either in your place of employment or at home? If so, I would love to hear about it on the comment boards.

You can reach Adam Ross at aross@nextgov.com.