7.3 Ensure 'Security Policy' denying any/all traffic exists at the bottom of the security policies ruleset

Information

EXTREME CAUTION MUST BE USED BEFORE IMPLEMENTING THIS RECOMMENDATION, AS CERTAIN TRAFFIC PERMITTED BY DEFAULT WILL BE DENIED UNLESS SPECIFICALLY ALLOWED.

Create a security rule at the bottom of the security policies ruleset denying any traffic, regardless of source, destination, or application. Ensure this policy is set to log at session end, just before pre-defined intrazone-default and interzone-default rules.
Rationale:
In incident response, logging denied traffic is often just as important as logging permitted traffic. The logs for denied traffic can be used to establish a pattern of failed attack attempts before the final attack succeeds. This can be used in attribution and identification of the attacker, but can also be used to help identify which defenses need shoring up to defend against future attacks. Viewing denied traffic can also be useful for understanding how security policies are affecting traffic.
Palo Alto firewalls do not log denied traffic by default. Therefore, to acquire visibility to denied traffic, a 'deny and log' policy must be created at the end of the security policy ruleset.

NOTE: Nessus has provided the target output to assist in reviewing the benchmark to ensure target compliance.

Solution

Navigate to Policies > Security.
Set a Security Policy with:

Name set to 'Deny and Log Any'

Source:
Zone set to Any
Address set to Any

Destination:
Zone set to Any
Address set to Any
Application set to Any
Service set to Any
Action set to Block
Profile set to None
Default Value:
Not Configured

See Also

https://workbench.cisecurity.org/files/1780

Item Details

Category: SYSTEM AND COMMUNICATIONS PROTECTION

References: 800-53|SC-7(5), CSCv6|6.5

Plugin: Palo_Alto

Control ID: 82160a14dab5770062d5c79e1ef791ce869e4d53cea83bace6888d007e4cc228