Protect yourself against future threats.
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AUSCERT External Security Bulletin Redistribution
ESB-2022.0129
Citrix Hypervisor Security Update
13 January 2022
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AusCERT Security Bulletin Summary
---------------------------------
Product: Citrix Hypervisor
Publisher: Citrix
Operating System: Citrix XenServer
Impact/Access: Denial of Service -- Existing Account
Reduced Security -- Existing Account
Resolution: Patch/Upgrade
CVE Names: CVE-2021-28715 CVE-2021-28714 CVE-2021-28705
CVE-2021-28704
Reference: ESB-2022.0121
ESB-2021.4326
ESB-2021.4113
ESB-2021.4111
ESB-2021.3983
Original Bulletin:
https://support.citrix.com/article/CTX335432
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Citrix Hypervisor Security Update
Reference: CTX335432
Category : Medium
Created : 12 January 2022
Modified : 12 January 2022
Applicable Products
o Citrix Hypervisor
Description of Problem
Several security issues have been identified in Citrix Hypervisor, that may
each allow privileged code in a guest VM to cause the host to crash or become
unresponsive.
These issues have the following identifiers:
o CVE-2021-28704
o CVE-2021-28705
o CVE-2021-28714
o CVE-2021-28715
All of these issues affect all currently supported versions of Citrix
Hypervisor.
What Customers Should Do
Citrix has released hotfixes to address these issues. 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 CU1 LTSR: CTX338448 - https://support.citrix.com/article/
CTX338448 and CTX335882 - https://support.citrix.com/article/CTX335882
Citrix Hypervisor 8.2: CTX338444 - https://support.citrix.com/article/CTX338444
and CTX335880 - https://support.citrix.com/article/CTX335880
Citrix XenServer 7.1 LTSR CU2: CTX335531 - https://support.citrix.com/article/
CTX335531 and CTX335881 - https://support.citrix.com/article/CTX335881
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 https://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/ .
Reporting Security Vulnerabilities to Citrix
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
2022-01-12 Initial Publication
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