Exception reboot

We have a Sonicwall on 6.5.4.5, and it experienced several reboots in the past few days. We would like to know what is "exception reboot" and "soft watchdog reboot" in the trace log likely means.
We can't open a case to Sonicwall due to it being end of support.
Category: Entry Level Firewalls
0
Answers
It means that something triggered a bug.
That firmware is ancient and will be vulnerable to [at a minimum] the SSLVPN vulnerabilities, which happen to cause reboots.