CMS CMS rights (Can publish)
 

I have assigned the 'Create Content' rights of the CMS to a user. I also assigned 'Can Publish' rights so the user can publish his own stuff. I didn't assign the 'Edit others' Content'. But if the Can Publish rights are assigned, the user is also able to modify/edit the content of others.

Is this by design that a 'Can Publish' right can modify/edit all content of all users or is it a bug?