Powershell v3 Invoke-WebRequest HTTPS error

Question

Using Powershell v3's Invoke-WebRequest and Invoke-RestMethod I have succesfully used the POST method to post a json file to a https website.

The command I'm using is

 $cert=New-Object System.Security.Cryptography.X509Certificates.X509Certificate2("cert.crt")
 Invoke-WebRequest -Uri https://IPADDRESS/resource -Credential $cred -certificate $cert -Body $json -ContentType application/json -Method POST

However when I attempt to use the GET method like:

 Invoke-WebRequest -Uri https://IPADDRESS/resource -Credential $cred -certificate $cert -Method GET

The following error is returned

 Invoke-RestMethod : The underlying connection was closed: An unexpected error occurred on a send.
 At line:8 char:11
 + $output = Invoke-RestMethod -Uri https://IPADDRESS/resource -Credential $cred
 +           ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ CategoryInfo          : InvalidOperation: (System.Net.HttpWebRequest:HttpWebRequest)      [Invoke-RestMethod], WebException
+ FullyQualifiedErrorId : WebCmdletWebResponseException,Microsoft.PowerShell.Commands.InvokeRestMethodCommand

I have attempted using the following code to ignore SSL cert, but I'm not sure if its actually doing anything.

 [System.Net.ServicePointManager]::ServerCertificateValidationCallback = {$true}

Can someone provide some guideance on what might be going wrong here and how to fix it?

Thanks

Answer 1

The following worked worked for me (and uses the latest non deprecated means to interact with the SSL Certs/callback functionality), and doesn't attempt to load the same code multiple times within the same powershell session:

if (-not ([System.Management.Automation.PSTypeName]'ServerCertificateValidationCallback').Type)
{
$certCallback=@"
    using System;
    using System.Net;
    using System.Net.Security;
    using System.Security.Cryptography.X509Certificates;
    public class ServerCertificateValidationCallback
    {
        public static void Ignore()
        {
            if(ServicePointManager.ServerCertificateValidationCallback ==null)
            {
                ServicePointManager.ServerCertificateValidationCallback += 
                    delegate
                    (
                        Object obj, 
                        X509Certificate certificate, 
                        X509Chain chain, 
                        SslPolicyErrors errors
                    )
                    {
                        return true;
                    };
            }
        }
    }
"@
    Add-Type $certCallback
 }
[ServerCertificateValidationCallback]::Ignore();

This was adapted from the following article https://d-fens.ch/2013/12/20/nobrainer-ssl-connection-error-when-using-powershell/

Answer 2

Lee's answer is great, but I also had issues with which protocols the web server supported.
After also adding the following lines, I could get the https request through. As pointed out in this answer https://stackoverflow.com/a/36266735

$AllProtocols = [System.Net.SecurityProtocolType]'Ssl3,Tls,Tls11,Tls12'
[System.Net.ServicePointManager]::SecurityProtocol = $AllProtocols

My full solution with Lee's code.

add-type @"
using System.Net;
using System.Security.Cryptography.X509Certificates;
public class TrustAllCertsPolicy : ICertificatePolicy {
    public bool CheckValidationResult(
        ServicePoint srvPoint, X509Certificate certificate,
        WebRequest request, int certificateProblem) {
        return true;
    }
}
"@
$AllProtocols = [System.Net.SecurityProtocolType]'Ssl3,Tls,Tls11,Tls12'
[System.Net.ServicePointManager]::SecurityProtocol = $AllProtocols
[System.Net.ServicePointManager]::CertificatePolicy = New-Object TrustAllCertsPolicy

Answer 3

If you run this as administrator, that error should go away