The earliest recollection of this bug is traced back to PAN-OS 11.1.3 - July 31, 2026. This bug is fixed in PAN-OS versions 11.1.5. On an NGFW cluster node, an expected packet buffer leak occurs with FTP/SIP traffic over an extended period of time. Fixed an issue where, on NFGW cluster nodes, an expected packet buffer leak occurred with FTP/SIP traffic over an extended period of time. In the event of a cluster manager restart on the leader node of an NGFW cluster, traffic stops because the state machine transitions to unknown and the leader is not changing. For more information: https://docs.paloaltonetworks.com/pan-os/11-1/pan-os-release-notes/pan-os-11-1-3-known-and-addressed-issues/pan-os-11-1-3-known-issues https://docs.paloaltonetworks.com/pan-os/11-1/pan-os-release-notes/pan-os-11-1-4-known-and-addressed-issues/pan-os-11-1-4-known-issues https://docs.paloaltonetworks.com/pan-os/11-1/pan-os-release-notes/pan-os-11-1-5-known-and-addressed-issues/pan-os-11-1-5-addressed-issues