The Walrus service in Eucalyptus 2.0.3 and 3.0.x before 3.0.2 allows remote attackers to gain administrator privileges via a crafted REST request.
https://euvd.enisa.europa.eu/vulnerability/EUVD-2012-3218
http://www.eucalyptus.com/eucalyptus-cloud/security/esa-03