Xen Denial of Service Vulnerability (XSA-301)

high Nessus Plugin ID 132934


The remote Xen hypervisor installation is missing a security update.


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 improper validation of input data. An authenticated, remote attack can exploit this, via a specially crafted hypercall followed by an access to an address that passes the sanity check but causes a hypervisor crash .

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.


Apply the appropiate patch according to the vendor advisory.

See Also


Plugin Details

Severity: High

ID: 132934

File Name: xen_server_XSA-301.nasl

Version: 1.3

Type: local

Family: Misc.

Published: 1/15/2020

Updated: 7/10/2020

Configuration: Enable paranoid mode

Risk Information

CVSS Score Source: CVE-2019-18423


Risk Factor: Medium

Score: 5.9


Risk Factor: High

Base Score: 8.5

Temporal Score: 6.3

Vector: AV:N/AC:M/Au:S/C:C/I:C/A:C

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


Risk Factor: High

Base Score: 8.8

Temporal Score: 7.7

Vector: CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/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: 10/31/2019

Vulnerability Publication Date: 10/31/2019

Reference Information

CVE: CVE-2019-18423

IAVB: 2019-B-0084-S