As annoying as it is for some, the configuration interface for Apple AirPort used a simple SNMP interface. Now, lots of SNMP software has had bugs and remote exploits, but all things being equal it's a much simpler interface to export and requires shipping less code, not least because it doesn't have to support a GUI, directly or indirectly.
That said, I always configure my WiFi router (AirPort or w'ever) in bridging mode and put them behind my gateway. And I try to disable any web GUI entirely if at all possible. People who use the built-in WiFi capabilities of their Cable or DSL modems are begging to be hacked.
Not really, CGI can be written in anything, shell scripting, C, whatever. But security-wise, it doesn't much matter the language because the programmers working on the web interfaces of such embedded devices rarely do a good job.
Considering the amount of crappy C most routers have, that's probably the least of your concerns.
Good luck configuring that with a mac....
Apart from Apple's and Google's idiotic antics, what routers require anything more than a browser to configure?