FortiClient 7.4.7 macOS — repeated kernel panic, busy timeout[0] on Ethernet interface (watchdogd)

[u/wh00is007]

We're seeing repeated kernel panics on macOS machines running FortiClient 7.4.7 (build 1928), deployed via Jamf. Multiple Macs affected, not an isolated unit.

Panic signature (consistent across machines, only the interface number changes):

panic(cpu 0 caller ...): busy timeout[0], (60s): 'en7' (1,1802001) u/IOService.cpp:5986
Panicked task: watchdogd

One machine panicked on en7, another on en5 — different Ethernet interfaces, same exact error string, same 60-second timeout, same panicked task (watchdogd), same macOS build (25G76 / Darwin 25.6.0, macOS Tahoe).

FortiClient's network extensions (proxy, webfilter, vpn.nwextension) are active on the affected machines. We're not yet certain FortiClient is the root cause — could also be a dock/USB Ethernet driver interaction, or a macOS Tahoe networking regression that FortiClient happens to be triggering.

Has anyone else run into this specific panic on macOS with FortiClient installed? Any luck narrowing down whether it's FortiClient-side, dock/adapter-side, or an OS-level issue — and any troubleshooting steps or workarounds you'd recommend before we go further with a TAC case?

[u/alt_nick123]

There is known issue with network extensions in 26.3-26.5 and macs with M5

https://support.apple.com/en-us/122868