topic Re: CRL revocation traffic identified as ms-update in General Topics

CRL revocation traffic identified as ms-update

Trond.Olsen — Mon, 01 Oct 2018 12:57:35 GMT

Is this an expected behaviour? We where somewhat surprised that the application included this traffic. It includes all SSL CRL traffic (like establishing remote desktop or visiting websites), independent if its related to Windows Update.

Re: CRL revocation traffic identified as ms-update

gwesson — Mon, 01 Oct 2018 21:24:16 GMT

I checked a couple firewall logs on my end, and don't see that same behavior. But most browsers will use OCSP instead if it is present in the certificate.

A CRL is just an HTTP GET request (unlike OCSP which is its own protocol on top of HTTP) so it doesn't have its own application in the App-ID database.

If it's only CRL requests that are triggering as ms-update, I'm not sure how that could happen outside of an app-override rule. It may help if you specify the PAN-OS version along with the APP-ID version that's installed on your firewall.

Re: CRL revocation traffic identified as ms-update

Trond.Olsen — Tue, 02 Oct 2018 06:53:44 GMT

We had a deny policy in place for ms-update for clients - to enforce SCCM distribution. I suspect this had an adverse affect on the clients - maybe affecting root certificate updates. For example, when establishing secure connection using RDP there where a 15-30 second delay. Using other https resources also resulted in similar delays. Immediately after disabling the deny policy this problem went away.

Our setup: PANOS 8.1.2, 8070-5032. No application overrides in use.