What permissions does an approver need to edit and approve a document?

Question

If an Approval workflow assigns a task to approve a document to a user, that user receives an email which prompts them to:

• review the document, and modify if necessary
• edit the task to show as approved

Does being assigned the approval task automatically elevate the user's permission levels in order to allow them to carry these actions out, or do they already need to have

• edit/approval permissions on the document?
• edit/approval permissions for the task?

Answer 1

There is no automatic elevation of rights.

I just assigned a task in a demo site to a visitor user. This user cannot even see the task itself...

I think users need at least edit rights on the task and approval rights on the documents list.

Answer 2

The workflow itself does not elevate the rights of the users permission levels (the workflow itself runs in the context of SHAREPOINT\System context)

The user in question would need edit permissions to the document library and the task list.

Answer 3

If the user has not proper rights, the workflow will not progress. It will throw an exception error. You can see it in the log file.