FreeBSD : xen-kernel -- Long latency populate-on-demand operation is not preemptible (83350009-881e-11e5-ab94-002590263bf5)

medium Nessus Plugin ID 86838
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Synopsis

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

Description

The Xen Project reports :

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 contents, create a situation where this search is a time-consuming linear scan of the guest's address space.

A malicious HVM guest administrator can cause a denial of service.
Specifically, prevent use of a physical CPU for a significant period.

Solution

Update the affected package.

See Also

http://xenbits.xen.org/xsa/advisory-150.html

http://www.nessus.org/u?5c6dca42

Plugin Details

Severity: Medium

ID: 86838

File Name: freebsd_pkg_83350009881e11e5ab94002590263bf5.nasl

Version: 2.4

Type: local

Published: 11/11/2015

Updated: 1/6/2021

Dependencies: ssh_get_info.nasl

Risk Information

VPR

Risk Factor: Medium

Score: 4

CVSS v2

Risk Factor: Medium

Base Score: 4.9

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

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: 11/11/2015

Vulnerability Publication Date: 10/29/2015

Reference Information

CVE: CVE-2015-7970