During the Christmas season and early into the new year, we noticed a sharp decrease in spam volume, perhaps as online criminals took a break from their malicious activities and popped the champagne to celebrate. It could also have been a time to regroup and plan new strategies for the upcoming year.
In any case, over the weekend we observed a large new campaign purporting to be an email from ‘Microsoft Security Office’ with a link to a full security report (Microsoft.report.doc). This was somewhat unexpected, as typically the malicious Office files are directly attached to the email. Instead, the files are hosted on various servers with a short time to live window.