Ubuntu Security Notice 6567-1 - Gaoning Pan and Xingwei Li discovered that QEMU incorrectly handled the USB xHCI controller device. A privileged guest attacker could possibly use this issue to cause QEMU to crash, leading to a denial of service. This issue only affected Ubuntu 20.04 LTS and Ubuntu 22.04 LTS. It was discovered that QEMU incorrectly handled the TCG Accelerator. A local attacker could use this issue to cause QEMU to crash, leading to a denial of service, or possibly execute arbitrary code and escalate privileges. This issue only affected Ubuntu 20.04 LTS.