Recent Microsoft Office Zero Day attacks spotted in the wild

April 14, 2017

Microsoft Office 2007 SP3, Microsoft Office 2010 SP2, Microsoft Office 2013 SP1, Microsoft Office 2016, Microsoft Windows Vista SP2, Windows Server 2008 SP2, Windows 7 SP1, Windows 8.1 allow remote attackers to execute arbitrary code via a crafted document, aka "Microsoft Office/WordPad Remote Code Execution Vulnerability w/Windows API."

The attack comes in the form of malicious word document with embedded malicious link in the objautlink object. The objautlink in rtf is an object type of OLE autolink. This link tries to connect to the attacker's webserver, and downloads malicious script.

Decoding the rtf files gives you the url(s) the attacker is trying to connect to.

The original rtf data:

Decoded to hex which further gives the URL:

Another example:

The malicious script:

SonicWALL Threat Research Team has researched this vulnerability and released following signature to protect their customers.

  • SPY 1446 :Malformed-File rtf.MP.17
  • GAV: CVE-2017-0199.A