bugzilla -- information leak

A Bugzilla Security Advisory reports:

When moving a bug from one product to another, an intermediate
page is displayed letting you select the groups the bug should
be restricted to in the new product. However, a regression in
the 3.4.x series made it ignore all groups which are not
available in both products. As a workaround, you had to move
the bug to the new product first and then restrict it to the
desired groups, in two distinct steps, which could make the bug
temporarily public.