CVE-2015-7835

The modl2entry function in arch/x86/mm.c in Xen 3.4 through 4.6.x does not properly validate level 2 page table entries, which allows local PV guest administrators to gain privileges via a crafted superpage mapping...

CVE-2015-7835: Improper Input Validation

The modl2entry function in arch/x86/mm.c in Xen 3.4 through 4.6.x does not properly validate level 2 page table entries, which allows local PV guest administrators to gain privileges via a crafted superpage mapping...

x86: Long latency populate-on-demand operation is not preemptible

ISSUE DESCRIPTION When running an HVM domain in Populate-on-Demand mode, Xen would sometimes search the domain for memory to reclaim, in response to demands for population of other pages in the same domain. This search runs without preemption. The guest can, by suitable arrangement of its memory...

x86: Uncontrolled creation of large page mappings by PV guests

ISSUE DESCRIPTION The code to validate level 2 page table entries is bypassed when certain conditions are satisfied. This means that a PV guest can create writeable mappings using super page mappings. Such writeable mappings can violate Xen intended invariants for pages which Xen is supposed to...

x86: populate-on-demand balloon size inaccuracy can crash guests

ISSUE DESCRIPTION The design of the memory populate-on-demand PoD system requires that a guest's memory ballooning driver reach its memory reduction target. The target is not entirely well-defined in terms of the information visible to the appropriate parts of the system, so some unknown set of...

SMA Solar Sunny WebBox Privilege Gain Vulnerability

The SMA Solar Sunny WebBox is a device from SMA Germany for remote monitoring and maintenance of medium and large PV plants. A security vulnerability exists in the SMA Solar Sunny WebBox, which can be exploited by remote attackers to gain access...

Use after free in QEMU/Xen block unplug protocol

ISSUE DESCRIPTION When unplugging an emulated block device the device was not fully unplugged, meaning a second unplug attempt would attempt to unplug the device a second time using a previously freed pointer. IMPACT An HVM guest which has access to an emulated IDE disk device may be able to...

QEMU heap overflow flaw while processing certain ATAPI commands.

ISSUE DESCRIPTION The QEMU security team has predisclosed the following advisory: A heap overflow flaw was found in the way QEMU's IDE subsystem handled I/O buffer access while processing certain ATAPI commands. A privileged guest user in a guest with CDROM drive enabled could potentially use thi...

FreeBSD : xen-kernel -- vulnerability in the iret hypercall handler (8c31b288-27ec-11e5-a4a5-002590263bf5)

The Xen Project reports : A buggy loop in Xen's compatiret function iterates the wrong way around a 32-bit index. Any 32-bit PV guest kernel can trigger this vulnerability by attempting a hypercalliret with EFLAGS.VM set. Given the use of get/putuser, and that the virtual addresses in question ar...

DEBIAN-CVE-2015-4164

The compatiret function in Xen 3.1 through 4.5 iterates the wrong way through a loop, which allows local 32-bit PV guest administrators to cause a denial of service large loop and system hang via a hypercalliret call with EFLAGS.VM set...

CVE-2015-4164

Vulnerability: CVE-2015-4164 affects Xen 3.1–4.5. The compat_iret function iterates the loop incorrectly, enabling local 32-bit PV guests to trigger a denial of service (large loop, system hang) via hypercall_iret when EFLAGS.VM is set. Exploitation status is not detailed in the provided document...

CVE-2015-4164

The compatiret function in Xen 3.1 through 4.5 iterates the wrong way through a loop, which allows local 32-bit PV guest administrators to cause a denial of service large loop and system hang via a hypercalliret call with EFLAGS.VM set...

CVE-2015-4164: Undefined Security Weakness

The compatiret function in Xen 3.1 through 4.5 iterates the wrong way through a loop, which allows local 32-bit PV guest administrators to cause a denial of service large loop and system hang via a hypercalliret call with EFLAGS.VM set...

vulnerability in the iret hypercall handler

ISSUE DESCRIPTION A buggy loop in Xen's compatiret function iterates the wrong way around a 32-bit index. Any 32-bit PV guest kernel can trigger this vulnerability by attempting a hypercalliret with EFLAGS.VM set. Given the use of get/putuser, and that the virtual addresses in question are...

xen-kernel -- vulnerability in the iret hypercall handler

The Xen Project reports: A buggy loop in Xen's compatiret function iterates the wrong way around a 32-bit index. Any 32-bit PV guest kernel can trigger this vulnerability by attempting a hypercalliret with EFLAGS.VM set. Given the use of get/putuser, and that the virtual addresses in question are...

kernel security and bug fix update

kernel 2.6.18-404.0.0.0.1 - net fix tcptrimhead James Li orabug 14512145, 19219078 - ocfs2: dlm: fix recovery hung Junxiao Bi orabug 13956772 - i386: fix MTRR code Zhenzhong Duan orabug 15862649 - oprofile x86, mm: Add getuserpagesfast orabug 14277030 - oprofile export getuserpagesfast function...

HVM qemu unexpectedly enabling emulated VGA graphics backends

ISSUE DESCRIPTION When instantiating an emulated VGA device for an x86 HVM guest qemu will by default enable a backend to expose that device, either SDL or VNC depending on the version of qemu and the build time configuration. The libxl toolstack library does not explicitly disable these default...

Excessive checking in compatibility mode hypercall argument translation

ISSUE DESCRIPTION The hypercall argument translation needed for 32-bit guests running on 64-bit hypervisors performs checks on the final register state. These checks cover all registers potentially holding hypercall arguments, not just the ones actually doing so for the hypercall being processed,...

CVE-2014-8594

The dommuupdate function in arch/x86/mm.c in Xen 4.x through 4.4.x does not properly restrict updates to only PV page tables, which allows remote PV guests to cause a denial of service NULL pointer dereference by leveraging hardware emulation services for HVM guests using Hardware Assisted Paging...

CVE-2014-8594

The dommuupdate function in arch/x86/mm.c in Xen 4.x through 4.4.x does not properly restrict updates to only PV page tables, which allows remote PV guests to cause a denial of service NULL pointer dereference by leveraging hardware emulation services for HVM guests using Hardware Assisted Paging...