Description of Problem
Several security issues have been identified that, collectively, may allow privileged code running in a guest VM to compromise the host or cause a denial of service.These vulnerabilities have the following identifiers:
CVE ID | Description | Vulnerability Type | Pre-conditions |
CVE-2020-29479 | An attacker with the ability to execute privileged mode code in a guest can compromise the host | CWE-707: Improper Neutralization | Administrator access in guest |
CVE-2020-29480 | An attacker with the ability to execute privileged mode code in a guest can read non-sensitive metadata about another guest | CWE-284: Improper Access Control | Administrator access in guest |
CVE-2020-29481 | An attacker with the ability to execute privileged mode code in a guest can read data previously shared, using the Xenstore API, between two other guests | CWE-664: Improper Control of a Resource Through its Lifetime | Administrator access in guest |
CVE-2020-29482 | An attacker with the ability to execute privileged mode code in a guest can perform a denial of service attack against the host | CWE-664: Improper Control of a Resource Through its Lifetime | Administrator access in guest |
CVE-2020-29485 | An attacker with the ability to execute privileged mode code in a guest can perform a denial of service attack against the host | CWE-664: Improper Control of a Resource Through its Lifetime | Administrator access in guest |
CVE-2020-29486 | An attacker with the ability to execute privileged mode code in a guest can perform a denial of service attack against the host or a selected other VM | CWE-664: Improper Control of a Resource Through its Lifetime | Administrator access in guest |
CVE-2020-29487 | An attacker with the ability to execute privileged mode code in a guest can perform a denial of service attack against the host | CWE-664: Improper Control of a Resource Through its Lifetime | Administrator access in guest |
CVE-2020-29568 | An attacker with the ability to execute privileged mode code in a guest can perform a denial of service attack against the host | CWE-664: Improper Control of a Resource Through its Lifetime | Administrator access in guest |
CVE-2020-29569 | An attacker with the ability to execute privileged mode code in a guest can perform a denial of service attack against the host | CWE-664: Improper Control of a Resource Through its Lifetime | Administrator access in guest |
CVE-2020-29570 | An attacker with the ability to execute privileged mode code in a guest can perform a denial of service attack against the host | CWE-664: Improper Control of a Resource Through its Lifetime | Administrator access in guest |
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 soon as practicable. The hotfixes can be downloaded from the following locations:Citrix Hypervisor 8.2 LTSR:
CTX286796 – https://support.citrix.com/article/CTX286796 and
CTX286800 – https://support.citrix.com/article/CTX286800 and
CTX286804 – https://support.citrix.com/article/CTX286804
Citrix Hypervisor 8.1:
CTX286795 – https://support.citrix.com/article/CTX286795 and
CTX286799 – https://support.citrix.com/article/CTX286799 and
CTX286803 – https://support.citrix.com/article/CTX286803
Citrix XenServer 7.1 LTSR CU2:
CTX286794 – https://support.citrix.com/article/CTX286794 and
CTX286798 – https://support.citrix.com/article/CTX286798 and
CTX286802 – https://support.citrix.com/article/CTX286802
Citrix XenServer 7.0:
CTX286793 – https://support.citrix.com/article/CTX286793 and
CTX286797 – https://support.citrix.com/article/CTX286797 and
CTX286801 – https://support.citrix.com/article/CTX286801
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 http://www.citrix.com/site/ss/supportContacts.asp.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.htmlDisclaimer
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 |
2020-12-15 | Initial Publication |