Modify ticket links via REST API

Hi. I have used the REST API to successfully create a RefersTo link to an existing ticket but it’s only possible for users with special rights. My question is:

What right does the user need to update ticket links?

I receive the following error: “RefersTo: Permission Denied” for some users.

I know it is possible if I set ModifyTicket right for the group the user belongs to, but I want to know if there is any finer right that is only related to creating links.

BTW, I’m using REST 1.0


AFAIK there is no finer right.

One option is to have the linked tickets be created in a different queue and limit who can create tickets in that queue