Xen Hypervisor I/O Intercept Code Hypervisor Stack Guest-to-Host Information Disclosure (XSA-239)

high Nessus Plugin ID 103974

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VPR Score: 7.3

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 an unspecified flaw in the hvmemul_do_io() function in arch/x86/hvm/emulate.c that is triggered as an internal structure may contain data from an uninitialized hypervisor stack slot. This may allow an attacker on the guest to gain access to potentially sensitive information from the host.

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-239.html

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

Plugin Details

Severity: High

ID: 103974

File Name: xen_server_XSA-239.nasl

Version: 1.6

Type: local

Family: Misc.

Published: 10/19/2017

Updated: 11/12/2019

Dependencies: xen_server_detect.nbin

Configuration: Enable paranoid mode

Risk Information

Risk Factor: High

VPR Score: 7.3

CVSS Score Source: CVE-2017-15595

CVSS v2.0

Base Score: 7.2

Temporal Score: 5.6

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

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

CVSS v3.0

Base Score: 8.8

Temporal Score: 7.9

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

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

Vulnerability Information

CPE: cpe:/o:xen:xen

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

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 10/12/2017

Vulnerability Publication Date: 10/12/2017

Reference Information

CVE: CVE-2017-15588, CVE-2017-15589, CVE-2017-15590, CVE-2017-15591, CVE-2017-15592, CVE-2017-15593, CVE-2017-15594, CVE-2017-15595, CVE-2017-15596

BID: 101490, 101496, 101500

IAVB: 2017-B-0142