The earliest recollection of this bug is traced back to PAN-OS 8.1.18 - July 22, 2025. This bug is fixed in PAN-OS versions 9.1.5, 8.1.18. A fix was made to address a vulnerability where Ethernet packets on PA-200, PA-220, PA-500, PA-800, PA-2000 Series, PA-3000 Series, PA-3200 Series, PA-5000 Series, PA-5200 Series, and PA-7000 Series firewalls were not cleared before the data frame was created ( CVE-2021-3031 ). For more information: https://docs.paloaltonetworks.com/pan-os/8-1/pan-os-release-notes/pan-os-8-1-addressed-issues/pan-os-8-1-18-addressed-issues https://docs.paloaltonetworks.com/pan-os/9-1/pan-os-release-notes/pan-os-9-1-addressed-issues/pan-os-9-1-5-addressed-issues