Creating a virtual that listens on all vlans via iControl REST

You should be able to create a VS manually with your desired setting and then do a GET to see how it should be formatted. I've been trying on v11.4.1 but seem to be getting authentication errors. Something like this should work;

curl -k -u username:password -X GET "https://'hostname_or_IP'/mgmt/tm/ltm/virtual"

As its all based on tmsh commands, I'd imagine what you need to pass is this (in addition to all the rest);

payload['vlans'] = 'default'