A memory-leak flaw was found in the Quick Emulator(QEMU) built with USB xHCI controller emulation support. The flaw could occur while doing a USB-device unplug operation. Unplugging the device repeatedly resulted in leaking host memory, which affected other services on the host. A privileged user inside the guest could exploit this flaw to cause a denial of service on the host or potentially crash the host’s QEMU process instance.