It's tax season once more and like the inevitable turning of the tide, there are several spam campaigns using this particular social engineering hook. In this spam campaign, the sender is posing as an agent of the Internal Revenue Service (IRS), and scaring recipients into opening their malicious attachments. It does this by threatening legal action for unpaid taxes and so on. The malicious attachment in this case is detected as BKDR_NOANCOOE.SM, which compromises the system security of any system it infects, and could present as financial loss to the user if it gets in.
As always, users should always be vigilant - even more during this season - and update their systems/security solutions to maximize their protection with these attacks. Trend Micro solutions block all the elements involved in this particular spam attack.