FreeBSD : xen-kernel -- x86 segment base write emulation lacking canonical address checks (53dbd096-ba4d-11e6-ae1b-002590263bf5)

Medium Nessus Plugin ID 95507


The remote FreeBSD host is missing a security-related update.


The Xen Project reports :

Both writes to the FS and GS register base MSRs as well as the WRFSBASE and WRGSBASE instructions require their input values to be canonical, or a #GP fault will be raised. When the use of those instructions by the hypervisor was enabled, the previous guard against #GP faults (having recovery code attached) was accidentally removed.

A malicious guest administrator can crash the host, leading to a DoS.


Update the affected package.

See Also

Plugin Details

Severity: Medium

ID: 95507

File Name: freebsd_pkg_53dbd096ba4d11e6ae1b002590263bf5.nasl

Version: $Revision: 3.3 $

Type: local

Published: 2016/12/05

Modified: 2017/01/30

Dependencies: 12634

Risk Information

Risk Factor: Medium


Base Score: 4.9

Vector: CVSS2#AV:L/AC:L/Au:N/C:N/I:N/A:C


Base Score: 6

Vector: CVSS:3.0/AV:L/AC:L/PR:H/UI:N/S:C/C:N/I:N/A:H

Vulnerability Information

CPE: p-cpe:/a:freebsd:freebsd:xen-kernel, cpe:/o:freebsd:freebsd

Required KB Items: Host/local_checks_enabled, Host/FreeBSD/release, Host/FreeBSD/pkg_info

Patch Publication Date: 2016/12/04

Vulnerability Publication Date: 2016/11/22

Reference Information

CVE: CVE-2016-9385