Emails are being sent claiming to be from USA’s IRS department. They claim to offer a $375 refund for filling out a form. The form is hosted on a hacked web site, not on the IRS’s web site. The form asks for a large amount of personal information including credit card numbers and PIN numbers. This information is collected (a trick known as phishing) and later used to commit identity theft (and effectively stealing your money).
When doing any taxes online please ensure the website is correct. See this earlier article on how to recognise deceptive domain names (URLs) and check for SSL certificates on the page (double click on the padlock icon in Internet Explorer, read who owns the site).
Good antivirus packages these days will also keep track of which web sites you go to and alert you if it’s a known fraud site. So it’s a good investment to purchase one.