topic Re: Application Blocking page for HTTPS traffic through Web Proxy in General Topics

Application Blocking page for HTTPS traffic through Web Proxy

licenselu — Tue, 20 Nov 2012 20:53:12 GMT

Hello,

I experienced an issue with 'application blocking page' for https traffic through web proxy.

The firewall is configured to decrypt the HTTPS traffic.

Layout : Client -- Palo Alto FW -- Web proxy (Squid)

If the traffic (https session like https://www.facebook.com) is sent directly to Internet, I receive the 'Application Blocked page' in the browser.

If the traffic goes through the proxy (explicit configuration in the browser), I don't receive the 'Application Blocked page' in the browser.

Is it the default behaviour ?

How can I change this ??

Regards,

Re: Application Blocking page for HTTPS traffic through Web Proxy

rmonvon — Tue, 20 Nov 2012 21:50:27 GMT

Hi HA...Are you matching the application & action=deny, or are you using URL filtering to match the domain and block?

Re: Application Blocking page for HTTPS traffic through Web Proxy

licenselu — Tue, 20 Nov 2012 21:57:48 GMT

Hello,

I match at the application layer.

Basically, at the end of the rule base, I have a rule which block everything.

In the traffic log file, I clearly see 'facebook-base', action : deny.

Regards,

Re: Application Blocking page for HTTPS traffic through Web Proxy

dburns — Tue, 20 Nov 2012 22:50:44 GMT

This is expected behavior.

When configuring file blocking or URL filtering profiles for a policy and the action Continue is configured to prompt users before downloading files or accessing certain URLs, the continue page will not appear when accessing HTTPS sites. This will occurs if the firewall is configured with SSL decryption and the user’s browser is using a proxy server. The only workaround for this issue at this time is to disable proxy on the browser. The browsers that were tested for this issue include Internet Explorer versions 7 and 8, other browsers may also have this issue.

I'll work on a getting this in our KB.

Thanks,

Dominic

PaloAlto Networks

Re: Application Blocking page for HTTPS traffic through Web Proxy

licenselu — Wed, 21 Nov 2012 09:16:47 GMT

Hello Dominic,

First, thanks for your help.

Any plan to change this behaviour in the future ??

Regards,

Hedi