FreeBSD : xen-kernel -- Uncontrolled creation of large page mappings by PV guests (3d9f6260-881d-11e5-ab94-002590263bf5)

high Nessus Plugin ID 86836
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Synopsis

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

Description

The Xen Project reports :

The code to validate level 2 page table entries is bypassed when certain conditions are satisfied. This means that a PV guest can create writable mappings using super page mappings. Such writable mappings can violate Xen intended invariants for pages which Xen is supposed to keep read-only. This is possible even if the 'allowsuperpage' command line option is not used.

Malicious PV guest administrators can escalate privilege so as to control the whole system.

Solution

Update the affected package.

See Also

http://xenbits.xen.org/xsa/advisory-148.html

http://www.nessus.org/u?78b746cc

Plugin Details

Severity: High

ID: 86836

File Name: freebsd_pkg_3d9f6260881d11e5ab94002590263bf5.nasl

Version: 2.5

Type: local

Published: 11/11/2015

Updated: 1/6/2021

Dependencies: ssh_get_info.nasl

Risk Information

VPR

Risk Factor: Medium

Score: 6.5

CVSS v2

Risk Factor: High

Base Score: 7.2

Vector: AV:L/AC:L/Au:N/C:C/I:C/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-2015-7835