If you are interested please vote! Future State: Add additional controls so the default sharing can be removed quickly, or set to a new default.
Current State: With Ad-Hoc tasks, the system was designed so that all teams and groups that the user is assigned to are given View Access to the Ad-Hoc task. The reasoning for this design is because Ad-Hoc tasks are mainly work related in 90% of cases they are used, according to the product team.
"https://support.workfront.com/hc/en-us/community/posts/115001956934-Control-Visibility-User-Ad-Hoc-Tasks-">
https://support.workfront.com/hc/en-us/community/posts/115001956934-Control-Visibility-User-Ad-Hoc-T... Susan
