Due to the recent expiration of the Sectigo RSA CA cert (https://support.sectigo.com/articles/Knowledge/Sectigo-AddTrust-External-CA-Root-Expiring-May-30-202...) and our Palo firewall SSL decryption policy configuration to block expired certificates we are noticing that any website that is publishing the old expired CA chain (for example netaoc.org.uk) is being blocked due to them publishing an expired cert.
This is obviously working as expected however it's difficult for me to come into contact with each website hosting one of these invalid CA chains to get them to resolve the issue while our users experience issues and I manually exclude the sites from decryption. I of course could turn off expired certificate blocking however this something I would rather not do.
I have noticed that web browsers like Chrome when not running through decryption are handling this issue just fine as they seem to look up the new correct CA certificate themselves and use that. Is there a way I can configure out Palo to act in the same way or am I stuck being reliant on the web admins of the individual sites to correct their chain issues?
Response to my case.
Engineering has identified on the fix, and it is coming in upcoming releases of all major releases ie. 8.1.15, 9.0.9, 9.1.3.
With the fix, we will evaluate the leaf node, and chain up to trust store.
Tentative ETA is around Mid-June.
I would also like to update you that we have put together a customer advisory if you would like to take a look -
Just wanted to chime in. We are also seeing the problem on many websites. If you wireshark the traffic and filter tls.handshake.type==11 you can see the cross certificate(s) and its expiration( signedCertificate>validity>notAfter). Sometimes its USERTrust RSA Certification Authority, sometimes its AddTrust External CA Root, sometimes its both. Don't trust things like Chrome's dev tools to see the offending certs, you need to wireshark the traffic from a machine that is *not* being decrypted.
I'm either telling people to fix their websites or patiently waiting for 8.1.15 and hopes it fixes the issue.
We upgraded to 8.1.15 yesterday and OCSP broke. Certificates signed by three different CA's were returning a status of 'unknown' and we block status unknown. We have been having this issue occur intermittently, so I'm unsure if it is related to the PAN-OS upgrade.
That being said, during our upgrade and testing window, we could visit the sites that were affected by the Sectigo chain issue. The other issues popped up as users started to come into the office on Monday and browse around.
Click Accept as Solution to acknowledge that the answer to your question has been provided.
The button appears next to the replies on topics you’ve started. The member who gave the solution and all future visitors to this topic will appreciate it!
These simple actions take just seconds of your time, but go a long way in showing appreciation for community members and the LIVEcommunity as a whole!
The LIVEcommunity thanks you for your participation!