PAN-OS 7.1 - SSL Decryption Issues

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Highlighted
L3 Networker

PAN-OS 7.1 - SSL Decryption Issues

I recently upgraded from PAN-OS 7.0.6 to 7.1.0 on a lab PA-200 appliance to start to test some of the features.  Right off the bat there seems to be an issue with SSL Decyrption.  As I stated in another post, I'm having issues with sites such as banking establishments, google earth, bing maps, etc. where the browser (chrome, edge, and IE tested) will hang, partially display data, and continue to load after the page is presented.   Disabling decryption immeidately resolves the problem.  Mind you, on 7.0.6, decryption is working without issue.

 

Anyone else that is testing PAN-OS 7.1 run into this issue?  

 

-Matt

Highlighted
L6 Presenter

Re: PAN-OS 7.1 - SSL Decryption Issues

Hi...There is a change to the policy behavior in 7.1 described here:  https://live.paloaltonetworks.com/t5/PAN-OS-7-1-Articles/PAN-OS-7-1-Policy-behavior-change-applicati...

 

Please double check your policy & maybe we just need to add port 443 to the security policy or not use Application=any.  

 

Thanks,

Highlighted
L3 Networker

Re: PAN-OS 7.1 - SSL Decryption Issues

by mlinsemier a moment ago

I read this, but I don't see, in this case, how it is applicable.

 

I have a global rule it looks like this:

 

Rule: Allow Inside --> Outside : Application:any Service: application-default

 

This means that ssl traffic (https) generated from the inside network to the outside network is only allowed over of the application-default port of ssl, which is 443.  I dont see why I would need to adjust this rule as the internet sites are not using non standard web-browsing and SSL ports.

 

Additionally, if i disable encryption, the rule above works without issue.  It's specifically decryption related and there is no way to select application when configuring an SSL Forwarder.  

 

-Matt

Highlighted
L6 Presenter

Re: PAN-OS 7.1 - SSL Decryption Issues

Let's say the traffic is HTTPS where the PA would decrypt the SSL and we have web-browsing running on port 443.  Your rule is allowing web-browsing on the default port, tcp/80, so it would not match the decrypted traffic, web-browsing on tcp/443.

Highlighted
L7 Applicator

Re: PAN-OS 7.1 - SSL Decryption Issues

I'm wondering if there is any plan to add port 443 to web-browsing default port list aswell. SSL decryption is so common nowadays that to create specific policy for that to allow web-browsing on 443 is kind of stupid.

Enterprise Architect @ Cloud Carib www.cloudcarib.com
ACE, PCNSE, PCNSI
Highlighted
L6 Presenter

Re: PAN-OS 7.1 - SSL Decryption Issues

I get what you're saying @Raido, but there's also an application "SSL."

 

Personally I'd rather be able to control policy down to the minute detail that I want to allow "Web-Browsing" w/o allowing access to "SSL" site.

 

So personally I don't mind where Palo is going here.

Highlighted
L7 Applicator

Re: PAN-OS 7.1 - SSL Decryption Issues

If in security policy you allow application web-browsing to specific site and don't add ssl then right after 3 way handshake Palo will identify what application it really is and no ssl is permitted if you have not specified so.

 

Currently minimum ruleset needs to be
application - any / service - application-default

application - web-browsing / service - tcp443

 

Adding 443 to web-browsing default port list would get rid of need for second rule.

Enterprise Architect @ Cloud Carib www.cloudcarib.com
ACE, PCNSE, PCNSI
Highlighted
L3 Networker

Re: PAN-OS 7.1 - SSL Decryption Issues

 

 

I guess I am confused.

 

My rule above, with decryption disabled, functions perfectly.  No traffic is dropped, all websites are working, etc.  This to me proves that the App-ID is properly identifying the traffic and that the traffic on application-default ports are fine.

 

As decryption is global, and is not applied to a specific security rule, how does the rule above suddenly stop working when encryption is enabled?  I dont see why I would have to add addtional rules with addtional service ports when the existing rules are already working.

 

Again, this seems pretty cut and dry to me that decryption is not working as intended.  I've had similar issues in 7.0.1 etc that acted the same way, all of them were resolved in 7.0.4+ and were decryption engine bugs.  


Perhaps you could give me an example of how I would configure it differently in 7.1 vs 7.0.6.

Highlighted
L6 Presenter

Re: PAN-OS 7.1 - SSL Decryption Issues

Can you add a new rule to allow web-browsing on port 443 to confirm please:

 

any any app=web-browsing service=tcp/443 action=allow

<your existing app=any service=app-default>

 

Let's find out if that works or not and we can discuss further.  Thanks.

Highlighted
L3 Networker

Re: PAN-OS 7.1 - SSL Decryption Issues

Like i suspected, and kind of was eluding too above, its does not seem to be a rule issue.  It does not even hit the new rule when its created.  Traffic to, in this case www.53.com, is only ssl.  it never hits the web-browsing app-id application, therefore never hits the new rule as it's not detecting web-browsing on 443, its detecting it as ssl.

 

53.jpg

 

In your example, if it was a rule issue with applciation-default of web-browsing not including 443 service, i would have issues regardless or enabling or disabling ssl decryption.  None of my other applications other than ssl are experiencing any types of issues, and ssl is only causing issues when decryption is turned on.

 

I feel like I have things configured how they should be.  It seems as if perhaps the best path is to open a support case with Palo Alto.


Matt

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