vulnerability

FreeBSD: VID-04cf89e3-5854-11e6-b334-002590263bf5 (CVE-2016-6259): xen-kernel -- x86: Missing SMAP whitelisting in 32-bit exception / event delivery

Severity
5
CVSS
(AV:L/AC:L/Au:N/C:N/I:N/A:C)
Published
Aug 2, 2016
Added
Dec 10, 2025
Modified
Dec 10, 2025

Description

The Xen Project reports: Supervisor Mode Access Prevention is a hardware feature designed to make an Operating System more robust, by raising a pagefault rather than accidentally following a pointer into userspace. However, legitimate accesses into userspace require whitelisting, and the exception delivery mechanism for 32bit PV guests wasn't whitelisted. A malicious 32-bit PV guest kernel can trigger a safety check, crashing the hypervisor and causing a denial of service to other VMs on the host.

Solution

freebsd-upgrade-package-xen-kernel
Title
NEW

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