Monday, April 14, 2014

CVE-2012-0158 in Mime HTML MSO format still baffles AV + MH370 Theme

When we started working on the research for this blog post we were exploring Malaysia Airlines Flight 370 (MH370) malware lures using Yara to flag samples in Cryptam with the following rule:

rule theme_MH370 {
    meta:
        author = "MalwareTracker.com"
        version = "1.0"
        date = "2014-04-09"
    strings:
        $callsign1 = "MH370" ascii wide nocase fullword
        $callsign2 = "MAS370" ascii wide nocase fullword
        $desc1 = "Flight 370" ascii wide nocase fullword
    condition:
        any of them
}




In addition to APT1 use of the lure in Word document 5e8d64185737f835318489fda46f31a6 dropping an updated version of Trojan Elise, we were surprised to see that one of the recent MH370 lures was a Mime MSO document exploiting MS Office Word vulnerability CVE-2012-0158 with 0 detection rate on VirusTotal dropping a variant of Vidgrab/Evilgrab. FireEye nicely covered a number of the MH370 campaigns in their March blog post.  However we could not find any references to the Mime MSO document MD5 0f765671a844190d74e985410fe31e8e "Where is MH370.doc" with 0/51 detection on VirusTotal.com in any other reporting. We were one of the first to previously report that Mime MSO files were being used to exploit CVE-2012-0158 in Word (August 30, 2013 Malware Tracker Blog CVE-2012-0158 exploit evades AV in Mime HTML format). At the end of this post we provide 4 other March 2014 0 detection file indicators from Cryptam samples to hopefully assist AV in improving detection rates for this threat.

 Sample current as of this post on VirusTotal


 Cryptam result showing CVE-2012-0158 plus a 256byte xored exe:




The CVE-2012-0158 trigger is not obfuscated but uses a class ID BDD1F04B-858B-11D1-B16A-00C0F0283628 to activate the vulnerable MSCOMCTL ActiveX control:

The class ID is disclosed in MS12-027 as vulnerable to CVE-2012-0158:



Other 0 detection samples:
517782778e296fade32ce3fd2330afc8 "0319 Montsame.doc" (mwtracker comment: Mongolia) 2014-03-20T02:14:45.000Z 0/50

f721f3a22ad26105a8894ce967c02e32 "內政部公文.doc" (mwtracker comment: Taiwan) 2014-03-10T00:22:23.000Z  0/50

f851e312899d11abe39390cb6a21f982 "保釣信頭2012.doc" (mwtracker comment: Taiwan) 2014-03-07 07:05:26 0/50

82542d9913301396f6f1a676c9b93f58 "Iltgeh huudas_revised.doc"  (mwtracker comment: Estonia) 2014-03-05 07:54:10 0/50



Some of the samples appear to drop a vidgrab/evilgrab variant and another not-yet-identified implant.


1 comment:

  1. Can you share how you got the RATs or provide sample beacon requests? After a base64 decode, it looks like the embedded doc was stripped by Microsoft Forefront

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