corporate network security threat

Corporate networks have been under attack for years, but hackers now see personal Web mail accounts as a way to get information that can help them sneak into computers that would otherwise be locked down. "People always think of these attacks as isolated cases, but they're more like a series of successful and failed attacks over a longer period of time," Villeneuve said. "It's not a one-off attack."

For example, in the Gmail phishing attacks, the hackers used a little-known Microsoft protocol to figure out what type of antivirus software their victims were using. By knowing what antivirus program they were up against, they could then build attack code and then test it against their target security software to be sure that it would go undetected.

And by trolling through their victims' email messages, the attackers could write believable-sounding messages that their targets would be more likely to click on or open up. That's how the victims lose control of their computers: by opening, for example, a specially written pdf document or by taking their browsers to a malicious website. "This is the latest version of State's joint statement,