Xen Hypervisor Multiple Vulnerabilities (XSA-231 - XSA-234)

high Nessus Plugin ID 103328
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Synopsis

The remote Xen hypervisor installation is missing a security update.

Description

According to its self-reported version number, the Xen hypervisor installed on the remote host is affected by multiple vulnerabilities :

- A flaw exists in the alloc_heap_pages() function due to improper handling when 'node >= MAX_NUMNODES'. A guest attacker can use crafted hypercalls to execute arbitrary code on the host system. (CVE-2017-14316)

- A double-free flaw exists in the domain_cleanup() function within 'xenstored_domain.c'. A local attacker can use this flaw to crash the xenstored daemon which potentially could cause a denial of service.
(CVE-2017-14317)

- A null pointer dereference flaw exists in the
__gnttab_cache_flush() function. An attacker could potentially leverage this flaw to crash the host system from a guest system. (CVE-2017-14318)

- A flaw exists within 'arch/x86/mm.c'. An attacker could leverage this vulnerability to gain elevated privileges on the host system from a guest system. (CVE-2017-14319)

Note that Nessus has checked the changeset versions based on the xen.git change log. Nessus did not check guest hardware configurations or if patches were applied manually to the source code before a recompile and reinstall.

Solution

Apply the appropriate patch according to the vendor advisory.

See Also

http://xenbits.xen.org/xsa/advisory-231.html

http://xenbits.xen.org/xsa/advisory-232.html

http://xenbits.xen.org/xsa/advisory-233.html

http://xenbits.xen.org/xsa/advisory-234.html

https://xenbits.xen.org/gitweb/?p=xen.git;a=summary

Plugin Details

Severity: High

ID: 103328

File Name: xen_server_XSA-234.nasl

Version: 1.7

Type: local

Family: Misc.

Published: 9/19/2017

Updated: 6/3/2021

Dependencies: xen_server_detect.nbin

Configuration: Enable paranoid mode

Risk Information

CVSS Score Source: CVE-2017-14319

VPR

Risk Factor: Medium

Score: 6.5

CVSS v2

Risk Factor: High

Base Score: 7.2

Temporal Score: 5.3

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

Temporal Vector: E:U/RL:OF/RC:C

CVSS v3

Risk Factor: High

Base Score: 8.8

Temporal Score: 7.7

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

Temporal Vector: E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/o:xen:xen

Required KB Items: installed_sw/Xen Hypervisor, Settings/ParanoidReport

Exploit Ease: No known exploits are available

Patch Publication Date: 9/12/2017

Vulnerability Publication Date: 9/12/2017

Reference Information

CVE: CVE-2017-14316, CVE-2017-14317, CVE-2017-14318, CVE-2017-14319

BID: 100817, 100818, 100819, 100826

IAVB: 2017-B-0128-S