The earliest recollection of this bug is traced back to PAN-OS 10.1.0 - July 22, 2025. In rare cases, a PA-5200 Series firewall (with an FE100 network processor) that has session offload enabled (default) incorrectly resets the UDP checksum of outgoing UDP packets. Workaround: In PAN-OS 8.0.6 and later releases, you can persistently disable session offload for only UDP traffic using the set session udp-off load no CLI command. 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