How to Test Threat Prevention Using a Web Browser

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This document describes a test to generate a "Generic Cross Site Scripting" event in the threat log.



  1. Create a policy that allows the web-browsing and SSL applications.
  2. Apply the DEFAULT Vulnerability Protection security profile associated with the policy.
  3. Go to any web page and look for an entry box that allows any typed entries.
  4. Enter the following text into the entry box: <script>alert(XSS Test)</script>
    For example, the following image shows the website with the given text entered into the "Search" box:
    In the example above, when Enter is pressed after entering the text, the browser was busy for a while before displaying a message that the connection was reset.
  5. Go to Monitor > Threat on the PAN-OS Web GUI, and an alert appears in the threat log. The action shows that a TCP RESET was sent to the server.

The global counters can also be viewed to confirm that the firewall has sent TCP reset packets:

> show counter global | match RST

flow_action_close      4       0 drop      flow      pktproc   TCP sessions closed via injecting RST


See Also

For additional examples: XSS Filter Evasion Cheat Sheet - OWASP

Threat Prevention Deployment Tech Note


owner: skrall


Nice option. By the way I stared wide-eyed in surprise when after checking the proposed string I tried a simple modification of it and the firewall did not realize at all:

Try                  "<script> alert(XSS Test) </script>"    (spaces between <script> tag and the content alert...)

instead of        "<script>alert(XSS Test)</script>"

I can believe this is happening... anyone can help me to properly understand this? otherwise I can think that Thread prevention protection is really easy jump over.

Best regards.