When an item has a creative commons license and the item is under embargo the DefaultEmbargoSetter will also remove the anonymous read rights from the creative commons bundle.
On the display item jsp it will attempt to retrieve the creative commons url (see lines below) and these will cause an authorize exception which in turn will lead to an internal system error (unless the admin is logged in).
String cc_url = CreativeCommons.getLicenseURL(item);
String cc_rdf = CreativeCommons.getLicenseRDF(item);
I have attached a patch to fix this issue (if required I am also willing to upload a script that can fix the permissions on these license bundles).