Tasks with no authentication can be accessed by any user who has the general task link, without the need of entering any credentials. Previously, due to lack of credentials, there was no way to associate test results with candidates.
With the v8.3.63 update, candidates will now be asked their name and email address when they try to access a public task. This information will be used to create tickets in the background, so when a candidate finishes a test, the administrators will be able to figure out who that result belongs to.
This change will not prevent users with the task link from accessing a task with no authentication method. The users will be able to access these tasks as many times as they want, which may result in organization credits being used up in an uncontrolled way.