{
  "version": "https://jsonfeed.org/version/1",
  "title": "Aside on sean mcelroy: out of band",
  "icon": "https://avatars.micro.blog/avatars/2026/24/1924798.jpg",
  "home_page_url": "https://blog.seanmcelroy.com/",
  "feed_url": "https://blog.seanmcelroy.com/feed.json",
  "items": [
      {
        "id": "http://seanmcelroy.micro.blog/2017/06/24/powershell-oneliner-to-find-outbound.html",
        "title": "PowerShell one-liner to find outbound connectivity via WinRM",
        "content_html": "<p>In controlled environments, it&rsquo;s useful to know when outbound connectivity is not restricted to a predefined list of required hosts, as many standards like PCI require.  Here&rsquo;s a helpful one-liner that will query your Active Directory instance for computer accounts that are enabled, and then for each of them try to connect to a site from that machine, as orchestrated by WinRM.  If you use this script, just know that you will probably see a sea of errors for machines that connect be reached from your source host via WinRM.  My go-to site for testing non-secure HTTP is asdf.com, but you could use anything target and port you desire based on what should not be allowed in your environment.  I have changed the snippet below to example.com (which will not work) so I don&rsquo;t spam the poor soul who runs asdf.com, but you should replace that with google.com or whatever host to which you wish to verify connectivity.</p>\n<pre>Invoke-Command -ComputerName (Get-ADComputer -Filter {Enabled -eq \"True\"}\n -Property Name,Enabled | foreach { $_.Name }) -ScriptBlock\n { Test-NetConnection -Port 80 \"example.com\" | Select TcpTestSucceeded }</pre>\n<p>The output will be dropped into look something like this:</p>\n<pre> TcpTestSucceeded PSComputerName RunspaceId \n ---------------- -------------- ---------- \n             True YOUR-HOST-1    d5fd044c-c268-460e-a274-d3253adc8ce2 \n             True YOUR-HOST-2    98206f71-80c1-4e7e-a467-fec489c542ee \n            False YOUR-HOST-3    d0b6cf57-e833-44a6-a7bb-aebd4d854b5c \n             True YOUR-HOST-4    14af618b-1ca7-4c1f-bb56-ce58dbd4af94</pre>\n<p>It&rsquo;s a great sanity check before an audit or after major changes to your network architecture or security controls.  Enjoy!</p>\n<p> </p>\n<p> </p>\n<p> </p>\n",
        "date_published": "2017-06-24T23:35:28+00:00",
        "url": "https://blog.seanmcelroy.com/2017/06/24/powershell-oneliner-to-find-outbound.html",
        "tags": ["Security","Programming","Aside"]
      }
  ]
}