The earliest recollection of this bug is traced back to PAN-OS 10.1.0 - June 11, 2025.
This bug is fixed in PAN-OS versions 10.1.1.
A Passive PA-5450 firewall in an Active/Passive HA pair will continue to process traffic even if its port(s) are in a Disabled state when the ports do not link up initially due to local or remote faults.
( Passive PA-5450 firewalls in an HA active/passive configuration only ) Fixed an issue where, when the ports do not link up initially due to local or remote faults, the firewall continued to process traffic even when its port(s) were in a Disabled state.
For more information:
https://docs.paloaltonetworks.com/pan-os/10-1/pan-os-release-notes/pan-os-10-1-0-known-and-addressed-issues/pan-os-10-1-0-known-issues
https://docs.paloaltonetworks.com/pan-os/10-1/pan-os-release-notes/pan-os-10-1-1-known-and-addressed-issues/pan-os-10-1-1-addressed-issues