Security → Re: Wireshark

does it do anything if you are on a switch (I mean yeah, it could sniff all the packets going on all the virtual machines on a physical one)

Yes you can port mirror then on the monitoring system use wire shark to sniff.

Don't you need some sort of administrative access to the switch? Its not like a vendor can plug in a laptop in the conference room and sniff out our emails during his powerpoint?

Yes you need admin access the the managed switch.

Managed switch is one thing, why would a standard switch even have an admin panel or anything controlling over the network? I can sniff my internal network via the router's switch.

I think a little more specific clarification is needed to discuss the depth's of sniffing.

The vendor should never be exposed to anything but a guest vlan/wlan.

And the OP's question might need explaining more, as there is a yes/no type answer to the question. Yes a VM will allow sniffed traffic. Will it allow all traffic to be sniffed? Depends on the network. Hence my comment initially on what is the network we are referring to from the OP, it is too broad a comment I'd think to give an exacting reply. Call me pedantic.