x86 HVM: Overflow of sh_ctxt->seg_reg[]

ISSUE DESCRIPTION x86 HVM guests running with shadow paging use a subset of the x86 emulator to handle the guest writing to its own pagetables. There are situations a guest can provoke which result in exceeding the space allocated for internal state. IMPACT A malicious HVM guest administrator can...

xen-kernel -- x86 HVM: Overflow of sh_ctxt->seg_reg[]

The Xen Project reports: x86 HVM guests running with shadow paging use a subset of the x86 emulator to handle the guest writing to its own pagetables. There are situations a guest can provoke which result in exceeding the space allocated for internal state. A malicious HVM guest administrator can...

xen-kernel -- x86: Mishandling of instruction pointer truncation during emulation

The Xen Project reports: When emulating HVM instructions, Xen uses a small i-cache for fetches from guest memory. The code that handles cache misses does not check if the address from which it fetched lies within the cache before blindly writing to it. As such it is possible for the guest to...

Debian DLA-571-1 : xen security update (Bunker Buster)

Multiple vulnerabilities have been discovered in the Xen hypervisor. The Common Vulnerabilities and Exposures project identifies the following problems : CVE-2014-3672 XSA-180 Andrew Sorensen discovered that a HVM domain can exhaust the hosts disk space by filling up the log file. CVE-2016-3158,...

The XEN virtual machine monitor appears“deadly”vulnerabilities-vulnerability warning-the black bar safety net

! XEN has always been known for high performance, less resource-intensive, win IBM, AMD, HP, Red Hat and Novell, and many other world-class hardware and software manufacturers of high recognition and strong support of many domestic and foreign enterprises and users to use XEN to build a...

OracleVM 3.2 : xen (OVMSA-2016-0090)

The remote OracleVM system is missing necessary patches to address critical security updates : - x86/HVM: correct CPUID leaf 80000008 handling - 6c733e54 xsa173010001-x86-HVM-correct-CPUID-leaf-80000008-handl ing.patch was based on upstream commit: ef437690af8b75e6758dce77af75a22b63982883 x86/HVM...

virtio: unbounded memory allocation issue

ISSUE DESCRIPTION A guest can submit virtio requests without bothering to wait for completion and is therefore not bound by virtqueue size. This requires reusing vring descriptors in more than one request, which is incorrect but possible. Processing a request allocates a VirtQueueElement and...

Xen security advisories XSA-1 8 2, and XSA-1 8 3-may be caused by a virtual machine penetration-vulnerability warning-the black bar safety net

Today the Xen Update 2 important patch announcement XSA-1 8 2, and XSA-1 8 3,wherein the XSA-1 8 2 can be caused directly by the virtual machine penetration,recommends the use of Xen PV mode the Cloud Platform as soon as possible to update the patch. XSA-1 8 2 description of the problem: Xen PV...

FreeBSD : xen-kernel -- x86 shadow pagetables: address width overflow (d51ced72-4212-11e6-942d-bc5ff45d0f28)

The Xen Project reports : In the x86 shadow pagetable code, the guest frame number of a superpage mapping is stored in a 32-bit field. If a shadowed guest can cause a superpage mapping of a guest-physical address at or above 2^44 to be shadowed, the top bits of the address will be lost, causing a...

Unrestricted qemu logging

ISSUE DESCRIPTION When the libxl toolstack launches qemu for HVM guests, it pipes the output of stderr to a file in /var/log/xen. This output is not rate-limited in any way. The guest can easily cause qemu to print messages to stderr, causing this file to become arbitrarily large. IMPACT The disk...

xen-tools -- Unrestricted qemu logging

The Xen Project reports: When the libxl toolstack launches qemu for HVM guests, it pipes the output of stderr to a file in /var/log/xen. This output is not rate-limited in any way. The guest can easily cause qemu to print messages to stderr, causing this file to become arbitrarily large. The disk...

QEMU: Banked access to VGA memory (VBE) uses inconsistent bounds checks

ISSUE DESCRIPTION Qemu VGA module allows banked access to video memory using the window at 0xa00000 and it supports different access modes with different address calculations. But an attacker can easily change access modes after setting the bank register. This is CVE-2016-3710. Qemu VGA module...

Debian DSA-3554-1 : xen - security update

Multiple vulnerabilities have been discovered in the Xen hypervisor. The Common Vulnerabilities and Exposures project identifies the following problems : - CVE-2016-3158, CVE-2016-3159 XSA-172 Jan Beulich from SUSE discovered that Xen does not properly handle writes to the hardware FSW.ES bit whe...

Debian Security Advisory DSA 3554-1 (xen - security update)

Multiple vulnerabilities have been discovered in the Xen hypervisor. The Common Vulnerabilities and Exposures project identifies the following problems: CVE-2016-3158, CVE-2016-3159 XSA-172 Jan Beulich from SUSE discovered that Xen does not properly handle writes to the hardware FSW.ES bit when...

DSA-3554-1 xen - security update

Bulletin has no description...

x86 shadow pagetables: address width overflow

ISSUE DESCRIPTION In the x86 shadow pagetable code, the guest frame number of a superpage mapping is stored in a 32-bit field. If a shadowed guest can cause a superpage mapping of a guest-physical address at or above 2^44 to be shadowed, the top bits of the address will be lost, causing an...

xen-kernel -- x86 shadow pagetables: address width overflow

The Xen Project reports: In the x86 shadow pagetable code, the guest frame number of a superpage mapping is stored in a 32-bit field. If a shadowed guest can cause a superpage mapping of a guest-physical address at or above 2^44 to be shadowed, the top bits of the address will be lost, causing an...

CVE-2015-8554

Buffer overflow in hw/pt-msi.c in Xen 4.6.x and earlier, when using the qemu-xen-traditional aka qemu-dm device model, allows local x86 HVM guest administrators to gain privileges by leveraging a system with access to a passed-through MSI-X capable physical PCI device and MSI-X table entries,...

Buffer overflow

Buffer overflow in hw/pt-msi.c in Xen 4.6.x and earlier, when using the qemu-xen-traditional aka qemu-dm device model, allows local x86 HVM guest administrators to gain privileges by leveraging a system with access to a passed-through MSI-X capable physical PCI device and MSI-X table entries,...

UBUNTU-CVE-2015-8554

Buffer overflow in hw/pt-msi.c in Xen 4.6.x and earlier, when using the qemu-xen-traditional aka qemu-dm device model, allows local x86 HVM guest administrators to gain privileges by leveraging a system with access to a passed-through MSI-X capable physical PCI device and MSI-X table entries,...