The qemuMigrationWaitForSpice function in qemu/qemu_migration.c in libvirt before 1.1.3 does not properly enter a monitor when performing seamless SPICE migration, which allows local users to cause a denial of service (NULL pointer dereference and libvirtd crash) by causing domblkstat to be called at the same time as the qemuMonitorGetSpiceMigrationStatus function.