XFF Value 1.1.1.1 when "Strip X-Forwarded-For Header" enabled

Andrew.Scott — Tue, 25 Feb 2020 16:02:18 GMT

Hello,

Looking for some help if possible?

Trying to set up XFF (PA-3250, 8.1.12), I have tried to set it up following this tutorial:

https://live.paloaltonetworks.com/t5/General-Topics/Configuring-XFF-logging-without-a-URL-Filtering-License/td-p/239987

The only part I have not configured is pushing the URL logs to the syslog server.

The problem is, when "Strip X-Forwarded-For Header" is enabled the URL Filtering monitor displays the XFF value as 1.1.1.1. I temporarily disabled this feature and the internal client was displayed as expected, however, we would want to strip it and not make this information public. As soon as I enabled the strip feature again the value changed back to 1.1.1.1. I would have expected the XFF value to be displayed as the internal address and then as it leaves the firewall this information will be stripped from the HTTP header?

The clients go through a proxy server (Smoothwall), then to the FW and out. We do not have access to the proxy but have been assured this has been set up correctly.

Is there something I am missing in the set up?

Any help would be greatly appreciated!

Thanks.

Re: XFF Value 1.1.1.1 when "Strip X-Forwarded-For Header" enabled

KevinChan31 — Mon, 02 Mar 2020 20:14:45 GMT

I have the same result.

If you enable "Use X-Forwarded-For Header in User-ID", you can see the real XFF IP under the source user column of the logs. Palo Alto should have showed the real XFF IP in the XFF field and silently stripped it on the way out.

topic XFF Value 1.1.1.1 when "Strip X-Forwarded-For Header" enabled in General Topics

XFF Value 1.1.1.1 when "Strip X-Forwarded-For Header" enabled

Re: XFF Value 1.1.1.1 when "Strip X-Forwarded-For Header" enabled