Pharming, whereby hackers direct users to phony sites and harvest their personal information, has seen 50 banks around the world attacked in the last week. 

The attack has now been shut down.
Hackers built a seperate look-alike web site, hosting malicious code exploiting a critical vulnerability in Microsoft software, for each institution and then lured users to the site.
An unpatched computer would download a Trojan horse, called "iexplorer.exe," which downloads five additional files from a server in Russia.
If a user with an infected PC then visited any of the targeted banking sites, they were redirected to a mock-up of the bank's Web site that collected their login credentials and transferred them to the Russian server. The user was then passed back to the legitimate site where they were already logged in, making the attack invisible.
The Web sites hosting the malicious code, d in Germany, Estonia and the UK, had been shut down by ISPs.