OpenStack Compute (Nova) Folsom, Grizzly, and earlier, when using Apache Qpid for the RPC backend, does not properly handle errors that occur during messaging, which allows remote attackers to cause a denial of service (connection pool consumption), as demonstrated using multiple requests that send long strings to an instance console and retrieving the console log.
https://bugzilla.redhat.com/show_bug.cgi?id=999271