Citrix XenServer Multiple Security Updates

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<h2> Description of Problem</h2>

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<p>A number of security vulnerabilities have been identified in Citrix XenServer that may allow a malicious administrator of an HVM guest VM to compromise the host.</p>
<p>These vulnerabilities affect all currently supported versions of Citrix XenServer up to and including Citrix XenServer 7.2.</p>
<p>The following vulnerabilities have been addressed:</p>
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<li>CVE-2017-7980: code execution via overflow in Cirrus Logic emulation</li>
<li>CVE-2017-15592: Incorrect handling of self-linear shadow mappings with translated guests</li>
<li>CVE-2017-17044: Infinite loop due to missing PoD error checking</li>
<li>CVE-2017-17045: Missing p2m error checking in PoD code</li>
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<h2> Mitigating Factors</h2>

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<p>Customers without HVM guests (i.e. PV guests only) are not affected by these issues.</p>
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<h2> What Customers Should Do</h2>

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<p>Hotfixes have been released to address these issues. Citrix strongly recommends that affected customers install these hotfixes as soon as possible. The hotfixes can be downloaded from the following locations:</p>
<p>Citrix XenServer 7.2: CTX229541 – <a href=“https://support.citrix.com/article/CTX229541”>https://support.citrix.com/article/CTX229541</a> and CTX230161 – <a href=“https://support.citrix.com/article/CTX230161”>https://support.citrix.com/article/CTX230161</a></p>
<p>Citrix XenServer 7.1 LTSR CU1: CTX229540 – <a href=“https://support.citrix.com/article/CTX229540”>https://support.citrix.com/article/CTX229540</a> and CTX230160 – <a href=“https://support.citrix.com/article/CTX230160”>https://support.citrix.com/article/CTX230160</a></p>
<p>Citrix XenServer 7.1 LTSR: CTX229545 – <a href=“https://support.citrix.com/article/CTX229545”>https://support.citrix.com/article/CTX229545</a> and CTX230159 – <a href=“https://support.citrix.com/article/CTX230159”>https://support.citrix.com/article/CTX230159</a></p>
<p>Citrix XenServer 7.0: CTX229539 – <a href=“https://support.citrix.com/article/CTX229539”>https://support.citrix.com/article/CTX229539</a> and CTX229544 – <a href=“https://support.citrix.com/article/CTX229544”>https://support.citrix.com/article/CTX229544</a></p>
<p>Citrix XenServer 6.5 SP1: CTX229543 – <a href=“https://support.citrix.com/article/CTX229543”>https://support.citrix.com/article/CTX229543</a></p>
<p>Citrix XenServer 6.2 SP1: CTX229096 – <a href=“https://support.citrix.com/article/CTX229096”>https://support.citrix.com/article/CTX229096</a></p>
<p>Citrix XenServer 6.0.2 Common Criteria: CTX229095 – <a href=“https://support.citrix.com/article/CTX229095”>https://support.citrix.com/article/CTX229095</a></p>
<p>Customers using the LivePatching feature of Citrix XenServer will not need to reboot servers to apply this hotfix but HVM guest VMs must either be rebooted or migrated to a server with the hotfix already applied for the hotfix to be fully effective.</p>
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<h2> What Citrix Is Doing</h2>

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<p>Citrix is notifying customers and channel partners about this potential security issue. This article is also available from the Citrix Knowledge Center at <u> <a href=“http://support.citrix.com/”>http://support.citrix.com/</a></u>.</p>
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<h2> Obtaining Support on This Issue</h2>

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<p>If you require technical assistance with this issue, please contact Citrix Technical Support. Contact details for Citrix Technical Support are available at <u> <a href=“https://www.citrix.com/support/open-a-support-case.html”>https://www.citrix.com/support/open-a-support-case.html</a></u>. </p>
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<h2> Reporting Security Vulnerabilities</h2>

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<p>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 – <a href=“http://support.citrix.com/article/CTX081743”>Reporting Security Issues to Citrix</a></p>
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<h2> Changelog</h2>

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<td>Date </td>
<td>Change</td>
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<td>1st December 2017</td>
<td>Initial publishing</td>
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