CVE-2011-1751 – qemu: acpi_piix4: missing hotplug check during device removal

https://notcve.org/view.php?id=CVE-2011-1751

The pciej_write function in hw/acpi_piix4.c in the PIIX4 Power Management emulation in qemu-kvm does not check if a device is hotpluggable before unplugging the PCI-ISA bridge, which allows privileged guest users to cause a denial of service (guest crash) and possibly execute arbitrary code by sending a crafted value to the 0xae08 (PCI_EJ_BASE) I/O port, which leads to a use-after-free related to "active qemu timers." La función pciej_write en hw/acpi_piix4.c en la emulación de PIIX4 Power Management en qemu-kvm no comprueba si un dispositivo es conectable en caliente antes de desconectar el puente PCI-ISA, lo que permite causar una denegación de servicio y posiblemente ejecutar código de su elección a los usuarios privilegiados invitados mediante el envío de un valor específico al puerto I/O 0xae08 (PCI_EJ_BASE), lo que provoca a un uso después de liberación relacionado con "temporizadores qemu activos". • http://blog.nelhage.com/2011/08/breaking-out-of-kvm http://git.kernel.org/?p=virt/kvm/qemu-kvm.git%3Ba=commit%3Bh=505597e4476a6bc219d0ec1362b760d71cb4fdca http://lists.nongnu.org/archive/html/qemu-devel/2011-05/msg01810.html http://lists.opensuse.org/opensuse-updates/2011-05/msg00043.html http://rhn.redhat.com/errata/RHSA-2011-0534.html http://secunia.com/advisories/44393 http://secunia.com/advisories/44458 http://secunia.com/advisories/44648 http://secunia.com/advisories/44658 • CWE-20: Improper Input Validation CWE-119: Improper Restriction of Operations within the Bounds of a Memory Buffer •