A spam campaign using emails that have Excel file (.xls) attachments (detected by Trend Micro as Trojan.XF.HIDDBOOK.THDBHBO) has been seen circulating and targeting users in Italy and some users in Germany and other countries.
The attachment appears blank when opened, but it has a sheet set to “hidden” that attempts to connect to a URL and download a file. Setting sheets to hidden is a documented feature.
Some of the subjects of the spam emails written in Italian involve topics such as the availability of a free service, correcting information, invoice details, order completion, and service assistance.
Source: Trend Micro