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Quick Test for Cisco IPS functionality

If you ever need to test a Cisco IPS is inspecting and blocking traffic after you have installed it here is a quick test you can perform.

Ideally you will have a web server behind the IPS you can test against else otherwise just setup on up quickly (google HFS for an awesome little tool).

Initially you should try reaching the URL of the webserver normally.  If you have set everything up correctly then you should have no issues.

Now in order to test the IPS blocking an attack simply append the following to the end of the URL "/../../windows/system32/cmd.exe".

The URL should now look like http://www.testurl.com/windows/system32/cmd.exe

You should now find that your request fails.  A quick look in the IPS event log will show that this fired the WWW WindowsNT cmd.exe rule.  It believes someone is attempting a buffer overflow error to obtain the command prompt and blocks it.

This is a nice simple test to ensure that the IPS is inspecting and blocking traffic.

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