A recently observed phishing campaign is targeting taxpayers in the United States in an attempt to infect their machines with a piece of malware named Amadey, Cofense security researchers have discovered.

Relatively new and fairly simple, the Amadey botnet is available for hire for cybercriminals. One of the threat groups to have used the botnet is TA505, which leveraged it to distribute the FlawedAmmy RAT and email stealers.

The phishing campaign, Cofense explains, employs emails purporting to be from the Internal Revenue Service (IRS) and claiming that the recipient is eligible for a tax refund. The message also presents a “one time username and password” and urges the user to click the “Login Right Here” button.

The button, however, is an embedded hyperlink that redirects to hxxp://yosemitemanagement[.]com/fonts/page5/, where a fake IRS login page is displayed, asking the user to enter the one-time password, the researchers reveal.