The earliest recollection of this bug is traced back to PAN-OS 10.2.10-h27 - November 24, 2025. This bug is fixed in PAN-OS versions 11.2.8, 10.2.10-h27, 11.2.7-h3, 10.2.14, 10.2.13-h16, 11.1.11, 10.2.13-h18. Fixed an issue where the firewall dropped GRE keepalive packets that were encapsulated under another GRE tunnel. For more information: https://docs.paloaltonetworks.com/pan-os/10-2/pan-os-release-notes/pan-os-10-2-10-known-and-addressed-issues/pan-os-10-2-10-h27-addressed-issues https://docs.paloaltonetworks.com/pan-os/10-2/pan-os-release-notes/pan-os-10-2-13-known-and-addressed-issues/pan-os-10-2-13-h16-addressed-issues https://docs.paloaltonetworks.com/pan-os/10-2/pan-os-release-notes/pan-os-10-2-13-known-and-addressed-issues/pan-os-10-2-13-h18-addressed-issues https://docs.paloaltonetworks.com/pan-os/10-2/pan-os-release-notes/pan-os-10-2-14-known-and-addressed-issues/pan-os-10-2-14-addressed-issues https://docs.paloaltonetworks.com/pan-os/11-1/pan-os-release-notes/pan-os-11-1-11-known-and-addressed-issues/pan-os-11-1-11-addressed-issues https://docs.paloaltonetworks.com/pan-os/11-2/pan-os-release-notes/pan-os-11-2-7-known-and-addressed-issues/pan-os-11-2-7-h3-addressed-issues https://docs.paloaltonetworks.com/pan-os/11-2/pan-os-release-notes/pan-os-11-2-8-known-and-addressed-issues/pan-os-11-2-8-addressed-issues