Nagios Support Forum

I have been informed by our security guru at my company that there are critical vulnerabilities with PHP.
We are currently running PHP v5.3.3 and he is stating it should be v5.5 or later.

I have been asked to open a ticket with NAGIOS to see if we can upgrade PHP without issue we are currently running NAGIOS XI 5.2.9

The main limitation for any Nagios product is SourceGuardian. With that in mind, you should be able to run Nagios XI up to PHP 5.6. Just need to make sure the SourceGuardian loader is installed along with your new PHP version (usually running a ./upgrade will reconcile this).