Citrix XenServer Multiple Infinite Loop Guest-to-Host DoS (CTX202583)

medium Nessus Plugin ID 87012
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Synopsis

The remote host is affected by multiple denial of service vulnerabilities.

Description

The version of Citrix XenServer running on the remote host is affected by multiple denial of service vulnerabilities :

- An infinite loop condition exists in the KVM subsystem that is triggered when handling a stream of #AC (Alignment Check) exceptions. A local attacker within a virtualized guest can exploit this to cause a host OS panic or hang, resulting in a denial of service condition. (CVE-2015-5307)

- An infinite loop condition exists in the KVM subsystem that is triggered when handling a stream of #DB (Debug) exceptions. A local attacker within a virtualized guest can exploit this to cause a host OS panic or hang, resulting in a denial of service condition.
(CVE-2015-8104)

Solution

Apply the relevant hotfix referenced in the vendor advisory.

See Also

https://support.citrix.com/article/CTX202583

Plugin Details

Severity: Medium

ID: 87012

File Name: citrix_xenserver_CTX202583.nasl

Version: 1.9

Type: local

Family: Misc.

Published: 11/23/2015

Updated: 11/20/2019

Dependencies: citrix_xenserver_version.nbin

Risk Information

CVSS Score Source: CVE-2015-5307

VPR

Risk Factor: Medium

Score: 4.5

CVSS v2

Risk Factor: Medium

Base Score: 4.9

Temporal Score: 3.6

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

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

CVSS v3

Risk Factor: Medium

Base Score: 6.8

Temporal Score: 5.9

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

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

Vulnerability Information

CPE: cpe:/a:citrix:xenserver

Required KB Items: Host/XenServer/version, Host/local_checks_enabled

Exploit Ease: No known exploits are available

Patch Publication Date: 11/10/2015

Vulnerability Publication Date: 11/9/2015

Reference Information

CVE: CVE-2015-5307, CVE-2015-8104

BID: 77524, 77528