The libxenlight (libxl) toolstack library in Xen 4.0.x, 4.1.x, and 4.2.x uses weak permissions for xenstore keys for paravirtualised and emulated serial console devices, which allows local guest administrators to modify the xenstore value via unspecified vectors.

Xen 4.0.x, 4.1.x, and 4.2.x does not properly restrict the contents of a XRSTOR, which allows local PV guest users to cause a denial of service (unhandled exception and hypervisor crash) via unspecified vectors.

Xen 4.0.x, 4.1.x, and 4.2.x, when running on AMD64 processors, only save/restore the FOP, FIP, and FDP x87 registers in FXSAVE/FXRSTOR when an exception is pending, which allows one domain to determine portions of the state of floating point instructions of other domains, which can be leveraged to obtain sensitive information such as cryptographic keys, a similar vulnerability to CVE-2006-1056. NOTE: this is the documented behavior of AMD64 processors, but it is inconsistent with Intel processors in a security-relevant fashion that was not addressed by the kernels.

Buffer overflow in the Python bindings for the xc_vcpu_setaffinity call in Xen 4.0.x, 4.1.x, and 4.2.x allows local administrators with permissions to configure VCPU affinity to cause a denial of service (memory corruption and xend toolstack crash) and possibly gain privileges via a crafted cpumap.

Multiple unspecified vulnerabilities in the Elf parser (libelf) in Xen 4.2.x and earlier allow local guest administrators with certain permissions to have an unspecified impact via a crafted kernel, related to "other problems" that are not CVE-2013-2194 or CVE-2013-2195.

The Elf parser (libelf) in Xen 4.2.x and earlier allow local guest administrators with certain permissions to have an unspecified impact via a crafted kernel, related to "pointer dereferences" involving unexpected calculations.

Multiple integer overflows in the Elf parser (libelf) in Xen 4.2.x and earlier allow local guest administrators with certain permissions to have an unspecified impact via a crafted kernel.

Xen 4.0.2 through 4.0.4, 4.1.x, and 4.2.x allows local PV guest users to cause a denial of service (hypervisor crash) via certain bit combinations to the XSETBV instruction.

Xen 4.0.x and 4.1.x incorrectly releases a grant reference when releasing a non-v1, non-transitive grant, which allows local guest administrators to cause a denial of service (host crash), obtain sensitive information, or possibly have other impacts via unspecified vectors.

Xen 4.x, when using Intel VT-d for a bus mastering capable PCI device, does not properly check the source when accessing a bridge device's interrupt remapping table entries for MSI interrupts, which allows local guest domains to cause a denial of service (interrupt injection) via unspecified vectors.

Xen 3.1 through 4.x, when running 64-bit hosts on Intel CPUs, does not clear the NT flag when using an IRET after a SYSENTER instruction, which allows PV guest users to cause a denial of service (hypervisor crash) by triggering a #GP fault, which is not properly handled by another IRET instruction.

Xen 4.2.x, 4.1.x, and earlier, when the hypervisor is running "under memory pressure" and the Xen Security Module (XSM) is enabled, uses the wrong ordering of operations when extending the per-domain event channel tracking table, which causes a use-after-free and allows local guest kernels to inject arbitrary events and gain privileges via unspecified vectors.

Multiple HVM control operations in Xen 3.4 through 4.2 allow local HVM guest OS administrators to cause a denial of service (physical CPU consumption) via a large input.

The (1) XENMEM_decrease_reservation, (2) XENMEM_populate_physmap, and (3) XENMEM_exchange hypercalls in Xen 4.2 and earlier allow local guest administrators to cause a denial of service (long loop and hang) via a crafted extent_order value.

The guest_physmap_mark_populate_on_demand function in Xen 4.2 and earlier does not properly unlock the subject GFNs when checking if they are in use, which allows local guest HVM administrators to cause a denial of service (hang) via unspecified vectors.

The XENMEM_exchange handler in Xen 4.2 and earlier does not properly check the memory address, which allows local PV guest OS administrators to cause a denial of service (crash) or possibly gain privileges via unspecified vectors that overwrite memory in the hypervisor reserved range.

Stack-based buffer overflow in the dirty video RAM tracking functionality in Xen 3.4 through 4.1 allows local HVM guest OS administrators to cause a denial of service (crash) via a large bitmap image.

Xen 4.x, when downgrading the grant table version, does not properly remove the status page from the tracking list when freeing the page, which allows local guest OS administrators to cause a denial of service (hypervisor crash) via unspecified vectors.

Xen 4.1.1 and earlier allows local guest OS kernels with control of a PCI[E] device to cause a denial of service (CPU consumption and host hang) via many crafted DMA requests that are denied by the IOMMU, which triggers a livelock.

The handle_mmio function in arch/x86/hvm/io.c in the MMIO operations emulator for Xen 3.3 and 4.x, when running an HVM guest, does not properly reset certain state information between emulation cycles, which allows local guest OS users to cause a denial of service (guest OS crash) via unspecified operations on MMIO regions.