Serious vulnerabilities that cannot be mitigated with a reasonable workaround will be addressed with a new firmware update as soon as possible.  For remaining vulnerabilities, please see Network Security Bulletins for mitigation steps.

Also, we recommend reading this: Best Practices to Secure Your Time Server.  Taking the steps outlined in this paper will eliminate most, if not all, vulnerabilities.  It was written for the Sonoma Time Servers but the same general steps apply to our other Linux-based products.