The one thing that is certain is the attacks are big.

"This is on a scale that is incredibly rare," said Mike Halsey, who runs The Long Climb, a PC support site in the U.K. "I don't think it's ever happened to this extent before, at least that I'm aware of."

A Fluid Situation

The situation is unfolding rapidly. Halsey said a couple of days ago the site www.neowin.net reported that PasteBin.com had posted personal details of about 20,000 users of Microsoft 's Hotmail, MSN and Windows Live services. Then on Tuesday, details about an additional 20,000 subscribers to Gmail, Yahoo, AOL Mail, Verizon and others were posted at the same site. The posts are now off-line.

It's possible the criminals have details on many more users that they haven't disclosed.

Details are sketchy, and there is no certainty that the problems are over. Sean-Paul Correll, a threat researcher with Panda Security, said he didn't see any of the data from the attacks. But he noted that phishing attacks are often precursors to other initiatives.

"It is fairly common that this would be the first stage of a larger attack. They use these e-mail addresses for something else," he said. Correll added that identifying what group or groups are responsible depends upon seeing more of the infrastructure -- such as the scripts they are using -- than just e-mail addresses. He wasn't sure what information might be available to researchers.

A Focus on Browser Security

The next move is up to the criminals. Halsey pointed out that browser security is vital and the size of the apparently ongoing phishing attacks should serve as a warning to browser vendors, including Microsoft, Opera, Apple and Mozilla. Luckily, these companies are focusing on improving the security of their products.

While Halsey isn't too worried about this week's activities, he is concerned about the long-term impact. "I would say this is probably isolated," he said of the phishing attacks. "The danger is that people pay a lot of attention when something like this is publicized but forget too quickly and do not learn. ... They shouldn't panic, or stop banking on the Internet or shopping on the Internet, as long as they are careful."

He added that good advice is available from a number of sources, including the British government, the FBI, and his site.

The key, according to Halsey, is to address the problem. "It is worrying from my point of view," he says. "It says people are not aware enough of what the threats are and that Internet service providers and major technology companies are not doing enough to warn people what the dangers are and how to avoid them, which is disappointing."