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AUSCERT External Security Bulletin Redistribution
ESB-2020.4014
Citrix Hypervisor Security Update
12 November 2020
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AusCERT Security Bulletin Summary
---------------------------------
Product: Citrix Hypervisor (formerly Citrix Xenserver)
Publisher: Citrix
Operating System: Citrix XenServer
Virtualisation
Impact/Access: Execute Arbitrary Code/Commands -- Existing Account
Increased Privileges -- Existing Account
Denial of Service -- Existing Account
Resolution: Patch/Upgrade
CVE Names: CVE-2020-27675 CVE-2020-27674 CVE-2020-27673
CVE-2020-27672 CVE-2020-27671 CVE-2020-27670
Reference: ESB-2020.3761
ESB-2020.3712
Original Bulletin:
https://support.citrix.com/article/CTX284874
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Citrix Hypervisor Security Update
Reference: CTX284874
Category : Medium
Created : 27 Oct 2020
Modified : 27 Oct 2020
Applicable Products
o Citrix Hypervisor
o XenServer
Description of Problem
Several security issues have been identified in Citrix Hypervisor (formerly
Citrix XenServer) that may allow:
o unprivileged code in a PV guest VM to compromise that PV guest VM
o privileged code in a guest VM to cause the host to crash or become
unresponsive
o privileged code in an HVM guest VM, to which the host administrator has
assigned a PCI passthrough device, to corrupt in-memory data of the host or
other VMs and potentially cause the host to crash.
These issues have the following identifiers:
o CVE-2020-27670
o CVE-2020-27671
o CVE-2020-27672
o CVE-2020-27673
o CVE-2020-27674
o CVE-2020-27675
These issues affect all currently supported versions of Citrix Hypervisor up to
and including Citrix Hypervisor 8.2 LTSR.
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 LTSR: CTX283510 - https://support.citrix.com/article/
CTX283510 and CTX283516 - https://support.citrix.com/article/CTX283516
Citrix Hypervisor 8.1: CTX283509 - https://support.citrix.com/article/CTX283509
and CTX283515 - https://support.citrix.com/article/CTX283515
Citrix XenServer 7.1 LTSR CU2: CTX283508 - https://support.citrix.com/article/
CTX283508 and CTX283514 - https://support.citrix.com/article/CTX283514
Citrix XenServer 7.0: CTX283507 - https://support.citrix.com/article/CTX283507
and CTX283512 - https://support.citrix.com/article/CTX283512
Changelog
+---------------------+-------------------------------------------------------+
|Date |Change |
+---------------------+-------------------------------------------------------+
|2020-10-27 |Initial Publication |
+---------------------+-------------------------------------------------------+
|2020-10-27 |Corrected links to hotfixes |
+---------------------+-------------------------------------------------------+
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===========================================================================
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The University of Queensland
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