usb-creator before 0.2.38.3ubuntu0.1 on Ubuntu 12.04 LTS, before 0.2.56.3ubuntu0.1 on Ubuntu 14.04 LTS, before 0.2.62ubuntu0.3 on Ubuntu 14.10, and before 0.2.67ubuntu0.1 on Ubuntu 15.04 allows local users to gain privileges by leveraging a missing call check_polkit for the KVMTest method.