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-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 =========================================================================== AUSCERT External Security Bulletin Redistribution ESB-2018.3624.2 Citrix XenServer Security Update 9 January 2019 =========================================================================== AusCERT Security Bulletin Summary --------------------------------- Product: Citrix XenServer Publisher: Citrix Operating System: Citrix XenServer Impact/Access: Root Compromise -- Existing Account Denial of Service -- Existing Account Resolution: Patch/Upgrade CVE Names: CVE-2018-19967 CVE-2018-19965 CVE-2018-19962 CVE-2018-19961 Reference: ESB-2019.0060 ESB-2019.0045 ESB-2019.0030 ESB-2018.3857 Original Bulletin: https://support.citrix.com/article/CTX239432 Revision History: January 9 2019: Updated CVE identifiers for TBA entries November 21 2018: Initial Release - --------------------------BEGIN INCLUDED TEXT-------------------- Citrix XenServer Security Update Created: 20 Nov 2018 | Modified: 08 Jan 2019 Applicable Products o XenServer 7.6 o XenServer 7.5 o XenServer 7.1 LTSR Cumulative Update 1 o XenServer 7.0 Description of Problem A number of security vulnerabilities have been identified in Citrix XenServer that have deployment-dependent impacts. These issues affect the following supported versions of Citrix XenServer: o Citrix XenServer 7.6 o Citrix XenServer 7.5 o Citrix XenServer 7.1 LTSR CU1 o Citrix XenServer 7.0 The following issues have been addressed: o CVE-2018-19961 / CVE-2018-19962: insufficient TLB flushing/improper large page mappings with AMD IOMMUs This issue may allow code in an HVM guest VM to compromise the host. This issue is limited to guests that are using the PCI passthrough feature in conjunction with AMD CPUs. o CVE-2018-19965: x86: DoS from attempting to use INVPCID with a non-canonical address This issue may allow privileged code in a PV guest VM to crash the host. This issue is limited to hosts with Intel CPUs that support the INVPCID instruction. This issue only occurs in Citrix XenServer 7.6. o CVE-2018-19967: Intel Erratum: "Processor May Hang When Executing Code In an HLE Transaction". This issue may allow code running in a guest VM to cause the host to become unresponsive and/or crash. This issue is limited to hosts with Intel CPUs that are affected by the corresponding Intel erratum. - ------------------------------------------------------------------------------- What Customers Should Do Hotfixes have been released to address these issues. Citrix recommends that affected customers install these hotfixes as their patching schedule permits. The hotfixes can be downloaded from the following locations: Citrix XenServer 7.6: CTX239437 - https://support.citrix.com/article/CTX239437 Citrix XenServer 7.5: CTX239436 - https://support.citrix.com/article/CTX239436 Citrix XenServer 7.1 LTSR CU1: CTX239435 - https://support.citrix.com/article/ CTX239435 Citrix XenServer 7.0: CTX239434 - https://support.citrix.com/article/CTX239434 - ------------------------------------------------------------------------------- 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 guidance on how to report security-related issues to Citrix, please see the following document: CTX081743 - - Reporting Security Issues to Citrix - ------------------------------------------------------------------------------- Changelog +------------------------+----------------------------------------------------+ |Date |Change | +------------------------+----------------------------------------------------+ |20th November 2018 |Initial Issue | +------------------------+----------------------------------------------------+ |8th January 2019 |Updated CVE identifiers for TBA entries | +------------------------+----------------------------------------------------+ - --------------------------END INCLUDED TEXT-------------------- You have received this e-mail bulletin as a result of your organisation's registration with AusCERT. The mailing list you are subscribed to is maintained within your organisation, so if you do not wish to continue receiving these bulletins you should contact your local IT manager. If you do not know who that is, please send an email to auscert@auscert.org.au and we will forward your request to the appropriate person. NOTE: Third Party Rights This security bulletin is provided as a service to AusCERT's members. As AusCERT did not write the document quoted above, AusCERT has had no control over its content. The decision to follow or act on information or advice contained in this security bulletin is the responsibility of each user or organisation, and should be considered in accordance with your organisation's site policies and procedures. AusCERT takes no responsibility for consequences which may arise from following or acting on information or advice contained in this security bulletin. NOTE: This is only the original release of the security bulletin. It may not be updated when updates to the original are made. If downloading at a later date, it is recommended that the bulletin is retrieved directly from the author's website to ensure that the information is still current. Contact information for the authors of the original document is included in the Security Bulletin above. If you have any questions or need further information, please contact them directly. Previous advisories and external security bulletins can be retrieved from: https://www.auscert.org.au/bulletins/ =========================================================================== Australian Computer Emergency Response Team The University of Queensland Brisbane Qld 4072 Internet Email: auscert@auscert.org.au Facsimile: (07) 3365 7031 Telephone: (07) 3365 4417 (International: +61 7 3365 4417) AusCERT personnel answer during Queensland business hours which are GMT+10:00 (AEST). On call after hours for member emergencies only. =========================================================================== -----BEGIN PGP SIGNATURE----- Comment: http://www.auscert.org.au/render.html?it=1967 iQIVAwUBXDV4M2aOgq3Tt24GAQj9nBAAyOh5JQK+xpwRdY9XWyKAuwi1yLmmuMe+ EEwYdviemieIUD9Mlui9YspE8IM9DA9qF1DiO0BL2sV49p9nkBR1cF8beEh++0v2 BJ33qyRSbV1UIa7QVSPbQDkXxk3UFf7JiS//0CVEGdX0bRaOE5Og/GgVGDfl93R9 FFYERKLcCxZq2OufgAzN3O6IGqrhb+uy071f+TK7xekgiCLBOQ9dVyw92Yw8T66b Kbkg4sXb3zu1zxWDg3kSiuwoZcl3yVyiLqVSbPS0/eVUbO/pxN78S+sFsc2/b1l1 7bhhjWkstbT7qObBX0Rd5spYT7QTmT2jP9a6kk8BaWEqPYUxpzjSvKGGbwhY218Z qMQxLdZNQhyx+UulvMqW29un+KQ3ceEq7Lwl4W+FR7jnqKzTFCySrGPXl53UjKdj 43GC7SQbXI0IN2NSdsXKf2Pq8vqcnIeumOufgcC31jxPDj1JloThqLjA4P0yIxOS g4cxLFImyRNOz4C8sCj34+bZ4FnFRCjXv/XPowOpNMy6LOBr3xCzPT/+7nE4qehk e5sptuaEWgN3bnCY+ra0+WrMYBs5cB04fBECCPewwHmir5Gw6ECXml7uDHM5lq3e N4WZmXZuLE9QNknu8UmGMfLQOYYGjno8ERWSPrUbqxtUSjDZuQjkQQcgwGDJcywS DB/gItNO/Vk= =Xin9 -----END PGP SIGNATURE-----