The earliest recollection of this bug is traced back to PAN-OS 8.1.10 - January 09, 2024. This bug is fixed in PAN-OS versions 8.1.10. ( PA-7000, PA-5200, and PA-3200 Series firewalls only ) Fixed an issue where the firewall dropped ICMP error messages when the security policy was configured to allow ICMP For more information: https://docs.paloaltonetworks.com/pan-os/8-1/pan-os-release-notes/pan-os-8-1-addressed-issues/pan-os-8-1-10-addressed-issues