Xen 4.4.x does not properly validate the load address for 64-bit ARM guest kernels, which allows local users to read system memory or cause a denial of service (crash) via a crafted kernel, which triggers a buffer overflow.

Xen 4.4.x does not properly check alignment, which allows local users to cause a denial of service (crash) via an unspecified field in a DTB header in a 32-bit guest kernel.

Buffer overflow in Xen 4.4.x allows local users to read system memory or cause a denial of service (crash) via a crafted 32-bit guest kernel, related to searching for an appended DTB.

The ARM image loading functionality in Xen 4.4.x does not properly validate kernel length, which allows local users to read system memory or cause a denial of service (crash) via a crafted 32-bit ARM guest kernel in an image, which triggers a buffer overflow.

xen: Unrestricted qemu logging

The qemu implementation in libvirt before 1.3.0 and Xen allows local guest OS users to cause a denial of service (host disk consumption) by writing to stdout or stderr.

xen: arm: Hardware timer context is not properly context switched (xsa-91)

Xen 4.4.x, when running on an ARM system, does not properly context switch the CNTKCTL_EL1 register, which allows local guest users to modify the hardware timers and cause a denial of service (crash) via unspecified vectors.

xen: hypervisor: HVMOP_set_mem_type allows invalid P2M entries to be created (XSA-92)

The HVMOP_set_mem_type control in Xen 4.1 through 4.4.x allows local guest HVM administrators to cause a denial of service (hypervisor crash) or possibly execute arbitrary code by leveraging a separate qemu-dm vulnerability to trigger invalid page table translations for unspecified memory page types.

The vgic_distr_mmio_write function in the virtual guest interrupt controller (GIC) distributor (arch/arm/vgic.c) in Xen 4.4.x, when running on an ARM system, allows local guest users to cause a denial of service (NULL pointer dereference and host crash) via unspecified vectors.

xen: Hardware features unintentionally exposed to guests on ARM

Xen 4.4.x, when running on ARM systems, does not properly restrict access to hardware features, which allows local guest users to cause a denial of service (host or guest crash) via unspecified vectors, related to (1) cache control, (2) coprocessors, (3) debug registers, and (4) other unspecified registers.

xen: HVMOP_set_mem_access is not preemptible

The HVMOP_set_mem_access HVM control operations in Xen 4.1.x for 32-bit and 4.1.x through 4.4.x for 64-bit allow local guest administrators to cause a denial of service (CPU consumption) by leveraging access to certain service domains for HVM guests and a large input.

kernel: xen: Linux netback crash trying to disable due to malformed packet

The netback driver in Xen, when using certain Linux versions that do not allow sleeping in softirq context, allows local guest administrators to cause a denial of service ("scheduling while atomic" error and host crash) via a malformed packet, which causes a mutex to be taken when trying to disable the interface.

xen: x86: Mishandling of instruction pointer truncation during emulation

Xen 4.5.3, 4.6.3, and 4.7.x allow local HVM guest OS administrators to overwrite hypervisor memory and consequently gain host OS privileges by leveraging mishandling of instruction pointer truncation during emulation.

xen: libvchan failure handling malicious ring indexes (xsa-86)

The (1) do_send and (2) do_recv functions in io.c in libvchan in Xen 4.2.x, 4.3.x, and 4.4-RC series allows local guests to cause a denial of service or possibly gain privileges via crafted xenstore ring indexes, which triggers a "read or write past the end of the ring."

xen: x86: Disallow L3 recursive pagetable for 32-bit PV guests

The get_page_from_l3e function in arch/x86/mm.c in Xen allows local 32-bit PV guest OS administrators to gain host OS privileges via vectors related to L3 recursive pagetables.

xen: x86: Missing SMAP whitelisting in 32-bit exception / event delivery (XSA-183)

Xen 4.5.x through 4.7.x do not implement Supervisor Mode Access Prevention (SMAP) whitelisting in 32-bit exception and event delivery, which allows local 32-bit PV guest OS kernels to cause a denial of service (hypervisor and VM crash) by triggering a safety check.

xen: Off-by-one error in FLASK_AVC_CACHESTAT hypercall (xsa-85)

Off-by-one error in the flask_security_avc_cachestats function in xsm/flask/flask_op.c in Xen 4.2.x and 4.3.x, when the maximum number of physical CPUs are in use, allows local users to cause a denial of service (host crash) or obtain sensitive information from hypervisor memory by leveraging a FLASK_AVC_CACHESTAT hypercall, which triggers a buffer over-read.

xen: x86: Privilege escalation in PV guests (XSA-182)

The PV pagetable code in arch/x86/mm.c in Xen 4.7.x and earlier allows local 32-bit PV guest OS administrators to gain host OS privileges by leveraging fast-paths for updating pagetable entries.

xen: arm: Host crash caused by VMID exhaustion (XSA-181)

The p2m_teardown function in arch/arm/p2m.c in Xen 4.4.x through 4.6.x allows local guest OS users with access to the driver domain to cause a denial of service (NULL pointer dereference and host OS crash) by creating concurrent domains and holding references to them, related to VMID exhaustion.

xen: integer overflow in several XSM/Flask hypercalls (xsa-84)

Multiple integer overflows in unspecified suboperations in the flask hypercall in Xen 3.2.x and earlier, when XSM is enabled, allow local users to cause a denial of service (processor fault) via unspecified vectors, a different vulnerability than CVE-2014-1891, CVE-2014-1892, and CVE-2014-1893.

xen: Unsanitised driver domain input in libxl device handling (XSA-178)

The libxl device-handling in Xen through 4.6.x allows local guest OS users with access to the driver domain to cause a denial of service (management tool confusion) by manipulating information in the backend directories in xenstore.