Hackers have flooded Internet with virus-tainted spam that targets Facebook’s estimated 400 million users in an effort to steal banking passwords and gather other sensitive information. The emails tell recipients that the passwords on their Facebook accounts have been reset, urging them to click on an attachment to obtain new login credentials, according to anti-virus software maker McAfee. If the attachment is opened, it downloads several types of malicious software, including a program that steals passwords, McAfee said on Wednesday. “With Facebook as your lure, you potentially have 400 million people that can click on the attachment. If you get 10 percent success, that’s 40 million,” Dave Marcus said. The email’s subject line says “Facebook password reset confirmation customer support,” according to Marcus. A Facebook spokesman said the company couldn’t comment on specific case, but pointed to a status update posted on its web site warning users about the spoofed email and advising users to delete the email and to warn their friends.