Responding to all subdomains


I’m having an issue with Virtualmin GPL, which I can’t get my head round. I own example.tld, and have virtualmin is set up on a VPS at vps.example.tld. I’ve also set up example.tld as a Virtual Server in Virtualmin, with web hosting on it.

As things stand at present, Webmin/Virtualmin will reply on ANYTHING.example.tld:10000 (well, anything that has an A-record).

Likewise, as well as responding on example.tld and www.example.tld like you’d expect, my website gets served on *.example.tld.

I’m aware that I can force Webmin to only respond on a given hostname, but haven’t found an answer to the hosting. There is an option in Website Settings for “Website matches all sub-domains?”, which is set to off.

I haven’t been able to test with another domain yet, as I’m still waiting on DNS to propogate.

Any idea what’s causing this?
Am I actually not allowed to have Webmin on the same domain as a Virtual Server?
Is there something blindingly obvious I’ve missed?