CVE-2016-9932

CMPXCHG8B emulation in Xen 3.3.x through 4.7.x on x86 systems allows local HVM guest OS users to obtain sensitive information from host stack memory via a "supposedly-ignored" operand size prefix...

CVE-2016-10025

VMFUNC emulation in Xen 4.6.x through 4.8.x on x86 systems using AMD virtualization extensions aka SVM allows local HVM guest OS users to cause a denial of service hypervisor crash by leveraging a missing NULL pointer check...

CVE-2016-10013

Xen through 4.8.x allows local 64-bit x86 HVM guest OS users to gain privileges by leveraging mishandling of SYSCALL singlestep during emulation...

CVE-2016-9382

Xen 4.0.x through 4.7.x mishandle x86 task switches to VM86 mode, which allows local 32-bit x86 HVM guest OS users to gain privileges or cause a denial of service guest OS crash by leveraging a guest operating system that uses hardware task switching and allows a new task to start in VM86 mode...

CVE-2016-9381

Race condition in QEMU in Xen allows local x86 HVM guest OS administrators to gain privileges by changing certain data on shared rings, aka a "double fetch" vulnerability...

UBUNTU-CVE-2016-9386

The x86 emulator in Xen does not properly treat x86 NULL segments as unusable when accessing memory, which might allow local HVM guest users to gain privileges via vectors involving "unexpected" base/limit values...

CVE-2016-9381

Race condition in QEMU in Xen allows local x86 HVM guest OS administrators to gain privileges by changing certain data on shared rings, aka a "double fetch" vulnerability...

CVE-2016-9381

Race condition in QEMU in Xen allows local x86 HVM guest OS administrators to gain privileges by changing certain data on shared rings, aka a "double fetch" vulnerability...

CVE-2016-9386

The x86 emulator in Xen does not properly treat x86 NULL segments as unusable when accessing memory, which might allow local HVM guest users to gain privileges via vectors involving "unexpected" base/limit values...

CVE-2016-9382

Xen 4.0.x through 4.7.x mishandle x86 task switches to VM86 mode, which allows local 32-bit x86 HVM guest OS users to gain privileges or cause a denial of service guest OS crash by leveraging a guest operating system that uses hardware task switching and allows a new task to start in VM86 mode...

CVE-2016-9382

CVE-2016-9382 affects Xen 4.0.x–4.7.x and is caused by mishandling x86 task switches to VM86 mode. Local 32-bit x86 HVM guests can either escalate privileges or cause a guest crash/DoS by leveraging hardware task switching and allowing a new task to start in VM86 mode. Public references describe ...

CVE-2016-9386

The x86 emulator in Xen does not properly treat x86 NULL segments as unusable when accessing memory, which might allow local HVM guest users to gain privileges via vectors involving "unexpected" base/limit values...

CVE-2016-9381

Race condition in QEMU in Xen allows local x86 HVM guest OS administrators to gain privileges by changing certain data on shared rings, aka a "double fetch" vulnerability...

x86: missing NULL pointer check in VMFUNC emulation

ISSUE DESCRIPTION When support for the Intel VMX VMFUNC leaf 0 was added, a new optional function pointer hvmemulvmfunc was added to the hvmemulateops table. As is intended, that new function pointer is NULL on non-VMX hardware, including AMD SVM hardware. However at a call site, the necessary NU...

x86: Mishandling of SYSCALL singlestep during emulation

ISSUE DESCRIPTION The typical behaviour of singlestepping exceptions is determined at the start of the instruction, with a DB trap being raised at the end of the instruction. SYSCALL and SYSRET, although we don't implement it behave differently because the typical behaviour allows userspace to...

CVE-2016-9932

CMPXCHG8B emulation in Xen 3.3.x through 4.7.x on x86 systems allows local HVM guest OS users to obtain sensitive information from host stack memory via a "supposedly-ignored" operand size prefix...

x86 CMPXCHG8B emulation fails to ignore operand size override

ISSUE DESCRIPTION The x86 instruction CMPXCHG8B is supposed to ignore legacy operand size overrides; it only honors the REX.W override making it CMPXCHG16B. So, the operand size is always 8 or 16. When support for CMPXCHG16B emulation was added to the instruction emulator, this restriction on the...

Debian DSA-3729-1 : xen - security update

Multiple vulnerabilities have been discovered in the Xen hypervisor. The Common Vulnerabilities and Exposures project identifies the following problems : - CVE-2016-7777 XSA-190 Jan Beulich from SUSE discovered that Xen does not properly honor CR0.TS and CR0.EM for x86 HVM guests, potentially...

qemu ioport array overflow

ISSUE DESCRIPTION The code in qemu which implements ioport read/write looks up the specified ioport address in a dispatch table. The argument to the dispatch function is a uint32t, and is used without a range check, even though the table has entries for only 2^16 ioports. When qemu is used as a...

FreeBSD : xen-kernel -- x86: Mishandling of instruction pointer truncation during emulation (49211361-ba4d-11e6-ae1b-002590263bf5)

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...