Heads-up: Dangerous new customized IRS scam steals data

The email is made out to a key financial contact here at Sunbelt (name obfuscated for this post).

As you can see, it’s quite convincing. (Incidentally, “Sunbelt Software Distribution, Inc.” is no longer our company name, it was recently changed to simply Sunbelt Software. But that’s a side note.)

Irscam1238888

Attached to the email is a zip file, which has a .scr file in it:

Taxrefundimage12388

Once clicked, the.scr file downloads several other files and reaches out to several servers including the "Office of the Attorney General - California Department of Justice" - where a PDF file is downloaded from and opened using your default PDF viewer.

In this case, we got a PDF from the following location:

http://ag(dot)ca(dot)gov/cms_pdfs/press/n1478_complaintat&tunauthorizedchargesfinal_tbf2.pdf?id=1594

Odf123777778

The entire purpose of this PDF is to make things look official. Otherwise, it’s meaningless, and does not appear to be malicious.

Interestingly, the id parameters for the PDF change with each install (increase in number) and the link is not indexed and the name of the PDF corresponds to the nature of the attack. And, interestingly, the malware set's its user agent to:

Accept-Encoding: identity

User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en;) Gecko/30060309

Firefox/1.5.0.7

This raises the question: Is this California .gov website compromised in some fashion to serve the pdf? We simply don’t know at this juncture, but this does look suspicious.

Then, a number of other URLs are contacted to download malware, and the user is left with keylogger on their system. It also appears that malware is downloaded from a number of compromised sites.