Xen Bad Continuation Handling in GNTTABOP_copy DoS (XSA-318)

medium Nessus Plugin ID 136189

Language:

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 in GNTTABOP_copy due to status fields of individual operations being left uninitialised. A buggy or malicious guest can construct its grant table in such a way that, when a backend domain tries to copy a grant, it hits the incorrect exit path. This returns success to the caller without doing anything, which may cause crashes or other incorrect behaviour.

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.

Plugin Details

Severity: Medium

ID: 136189

File Name: xen_server_XSA-318.nasl

Version: 1.4

Type: local

Family: Misc.

Published: 5/1/2020

Updated: 1/8/2021

Configuration: Enable paranoid mode

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Low

Score: 3.6

CVSS v2

Risk Factor: Low

Base Score: 2.1

Temporal Score: 1.6

Vector: CVSS2#AV:L/AC:L/Au:N/C:N/I:N/A:P

CVSS Score Source: CVE-2020-11742

CVSS v3

Risk Factor: Medium

Base Score: 5.5

Temporal Score: 4.8

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

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/o:xen:xen

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

Exploit Ease: No known exploits are available

Patch Publication Date: 4/14/2020

Vulnerability Publication Date: 4/14/2020

Reference Information

CVE: CVE-2020-11742

IAVB: 2020-B-0023-S

Detections

Analytics