ISE: 'Can't call method "is_auto_editor"' when attaching a TOC

Trying to attach a CD TOC when not logged in results in an ISE:

Error:
Caught exception in MusicBrainz::Server::Controller::CDTOC->attach "Can't call method "is_auto_editor" on an undefined value at lib/MusicBrainz/Server/Form/Role/Edit.pm line 18."

Stack trace:
line 18 MusicBrainz::Server::Form::Role::Edit
line 227 MusicBrainz::Server
line 126 MusicBrainz::Server::Controller
line 184 MusicBrainz::Server::Controller::CDTOC
line 316 MusicBrainz::Server
line 316 MusicBrainz::Server
line 316 MusicBrainz::Server
line 280 MusicBrainz::Server

Request data:

$VAR1 = {
'query_parameters' =>

{ 'artist' => '2062', 'medium' => '1081883', 'toc' => '1 13 341054 150 62746 81823 99207 118312 145494 165423 191474 210798 228499 251443 276992 308848' }

,
'body_parameters' => {}
};

URL: http://musicbrainz.org/cdtoc/attach?toc=1+13+341054+150+62746+81823+99207+118312+145494+165423+191474+210798+228499+251443+276992+308848&artist=2062&medium=1081883