Xen OOM DoS (XSA-349)

medium Nessus Plugin ID 145546
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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 a denial of service vulnerability due to an issue with the watch event queue. A malicious guest can exploit this, by abusing the unbounded queue, to cause an out-of-memory error in the backend, which can result in a DoS condition.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

Solution

Apply the appropriate patch or workaround according to the vendor advisory.

See Also

https://xenbits.xen.org/xsa/advisory-349.html

Plugin Details

Severity: Medium

ID: 145546

File Name: xen_server_XSA-349.nasl

Version: 1.3

Type: local

Family: Misc.

Published: 1/29/2021

Updated: 6/3/2021

Dependencies: xen_server_detect.nbin

Configuration: Enable paranoid mode

Risk Information

CVSS Score Source: CVE-2020-29568

VPR

Risk Factor: Medium

Score: 4.4

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: 6.5

Temporal Score: 5.7

Vector: CVSS:3.0/AV:L/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:/o:xen:xen

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

Exploit Ease: No known exploits are available

Patch Publication Date: 12/15/2020

Vulnerability Publication Date: 12/15/2020

Reference Information

CVE: CVE-2020-29568

IAVB: 2020-B-0077-S