Sophos is warning users from the US to be on the lookout for malicious emails purporting to hold important tax-related documents.
Entitled “FW: 2010 and 2011 Tax Documents; Accountant's Letter,” the emails read:
“I forward this file to you for review. Please open and view it. Attached are Individual Income Tax Returns and W-2s for 2010 and 2011, plus an accountant's letter.
This email message may include single or multiple file attachments of varying types. It has been MIME encoded for Internet e-mail transmission.”
The attachment is a zip archive which contains an executable named “Individual Income Tax Returns.exe.” The file actually hides a backdoor Trojan detected by Sophos solutions as Troj/Agent-ZWM.
Once it finds itself on a computer, the malware allows the cybercriminal that controls it to steal sensitive information from the infected device.
Users are advised to keep their antivirus solutions updated at all times and avoid opening suspicious attachments.