Malware spam: "Final Notice About Unpaid Bill" / "Important Notice About Created Invoice" / "Important Message About New Invoice"

This fake financial spam comes with a malicious attachment.The sender's name, subject and body text has a variety of text in, including:

Subject:
Fwd: Final Notice About Unpaid Bill
Fw: Important Notice About Created Invoice
Re: Important Message About New Invoice

Body text:
Pls see the bill attached.
review the report attached.
check the invoice attached.

Some more examples can be seen here.

Attached is a randomly-named document, of which I have seen three samples (VirusTotal results [1] [2] [3]). The Malwr report on one of the samples plus these Hybrid Analysis reports [4] [5] [6] shows a download of an encrypted file from:

darrallmacqueen.com/b2.jpg?XhVee=9
darrallmacqueen.com/b2.jpg?XhVee=20
darrallmacqueen.com/b2.jpg?XhVee=16

The dropped files seem pretty random, indeed in all the samples the binaries were different with some generic detections [1] [2] [3] [4]. All of the samples crash in Malwr [5] [6] [7] [8].

It all seems a little odd and if I get more information on what is happening, I will update this post. In the meantime the only mitigating step I can think of is to block traffic to darrallmacqueen.com which should stop the files downloading.