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                             CERT-Renater

                 Note d'Information No. 2020/VULN643
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DATE                : 25/11/2020

HARDWARE PLATFORM(S): /

OPERATING SYSTEM(S): Systems running Citrix Hypervisor,
                                  Citrix XenServer.

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https://support.citrix.com/article/CTX286511
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CTX286511
Citrix Hypervisor Security Update
Security Bulletin | Medium | Created: 24 Nov 2020 | Modified: 24 Nov 2020

Applicable Products
    Citrix Hypervisor XenServer


Description of Problem

A security issue has been identified that may allow privileged code
running in a guest VM to compromise the host.  This issue is limited to
only those guest VMs where the host administrator has explicitly
assigned a PCI passthrough device to the guest VM.

A CVE identifier for this issue is not yet available.

CVE ID 	Description 	Vulnerability Type 	Pre-conditions
TBA 	Bounding error updating physmap 	CWE-121 	A PCI passthrough device
must be assigned


This issue affects all currently supported versions of Citrix Hypervisor
up to and including Citrix Hypervisor 8.2 LTSR.


Mitigating Factors

Customers who are not using the PCI passthrough feature of Citrix
Hypervisor are not at risk from this issue

What Customers Should Do

Citrix has released hotfixes to address this issue. Citrix recommends
that affected customers install these hotfixes as their patching
schedule allows.  The hotfixes can be downloaded from the following
locations:
Citrix Hypervisor 8.2 LTSR: CTX286459 –
https://support.citrix.com/article/CTX286459
Citrix Hypervisor 8.1: CTX286458 –
https://support.citrix.com/article/CTX286458
Citrix XenServer 7.1 LTSR CU2: CTX286457 –
https://support.citrix.com/article/CTX286457
Citrix XenServer 7.0: CTX286456 –
https://support.citrix.com/article/CTX286456


What Citrix Is Doing

Citrix is notifying customers and channel partners about this potential
security issue. This article is also available from the Citrix Knowledge
Center at http://support.citrix.com/.

Obtaining Support on This Issue

If you require technical assistance with this issue, please contact
Citrix Technical Support. Contact details for Citrix Technical Support
are available at
https://www.citrix.com/support/open-a-support-case.html.


Reporting Security Vulnerabilities

Citrix welcomes input regarding the security of its products and
considers any and all potential vulnerabilities seriously. For details
on our vulnerability response process and guidance on how to report
security-related issues to Citrix, please see the following webpage: –
https://www.citrix.com/about/trust-center/vulnerability-process.html


Disclaimer

This document is provided on an "as is" basis and does not imply any
kind of guarantee or warranty, including the warranties of
merchantability or fitness for a particular use. Your use of the
information on the document is at your own risk. Citrix reserves the
right to change or update this document at any time.


Changelog

Date            Change
2020-11-24      Initial Publication

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+ CERT-RENATER       |    tel : 01-53-94-20-44          +
+ 23/25 Rue Daviel   |    fax : 01-53-94-20-41          +
+ 75013 Paris        |    email:cert@support.renater.fr +
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