The hvmmsrread_intercept function in arch/x86/hvm/hvm.c in Xen 4.1 through 4.4.x uses an improper MSR range for x2APIC emulation, which allows local HVM guests to cause a denial of service (host crash) or read data from the hypervisor or other guests via unspecified vectors.
{ "availability": "No subscription required", "ubuntu_priority": "medium", "binaries": [ { "libxenstore3.0": "4.4.0-0ubuntu5.2", "libxen-4.4": "4.4.0-0ubuntu5.2", "libxen-ocaml-dev": "4.4.0-0ubuntu5.2", "libxen-dev": "4.4.0-0ubuntu5.2", "xen-hypervisor-4.3-amd64": "4.4.0-0ubuntu5.2", "xen-hypervisor-4.3-armhf": "4.4.0-0ubuntu5.2", "xen-system-amd64": "4.4.0-0ubuntu5.2", "xen-hypervisor-4.4-arm64": "4.4.0-0ubuntu5.2", "libxen-ocaml": "4.4.0-0ubuntu5.2", "xenstore-utils": "4.4.0-0ubuntu5.2", "xen-system-armhf": "4.4.0-0ubuntu5.2", "xen-hypervisor-4.1-amd64": "4.4.0-0ubuntu5.2", "xen-hypervisor-4.4-armhf": "4.4.0-0ubuntu5.2", "xen-hypervisor-4.4-amd64": "4.4.0-0ubuntu5.2", "xen-utils-common": "4.4.0-0ubuntu5.2", "xen-utils-4.4": "4.4.0-0ubuntu5.2", "xen-system-arm64": "4.4.0-0ubuntu5.2" } ] }