Want to be able to have external contractors work on "bugs"

Want to be able to have external contractors work on "bugs"

We have multiple projects each which may have an outside contractor handling simple things such as user password issues etc.   We'd like to run all of this through Zoho, but don't want those contractors to have access to see larger issues we are tracking against those projects. 

We'd really like to be able to map such issues so that we can see them in Zoho and they just go out as an email to our "contractor".   Can this be done with the current Bug Tracker product?