Back to vendor advisories
Citrix Security BulletinsCTX695195

XenServer Security Update for CVE-2025-27466, CVE-2025-58142, CVE-2025-58143 and CVE-2025-58146

Several issues have been identified in XenServer 8.4 that collectively may allow privileged code in a guest VM to compromise or crash the host.

HighCVSS not listedHigh severity
Scope

What the vendor says is affected

  • XenServer
  • These issues affect XenServer 8.4. (Note that Citrix Hypervisor 8.2 CU1 is now End of Life (EoL) and so no longer receives security updates or security bulletins.)
Next step

What the vendor recommends

We have pushed updates to both the Early Access and Normal update channels of XenServer 8.4. We recommend that customers update to the latest version from their chosen channel following the instructions at https://docs.xenserver.com/en-us/xenserver/8/update What We Are Doing We are notifying customers and channel partners about this potential security issue through the publication of this security bulletin on the Citrix Knowledge Center at https://support.citrix.com/securitybulletins 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 Subscribe to Receive Alerts We strongly recommend that all customers subscribe to receive alerts when a security bulletin is created or modified at https://support.citrix.com/user/alerts Reporting Security Vulnerabilities to Us We welcome input regarding the security of our products and consider any and all potential vulnerabilities seriously. For details on our vulnerability response process and guidance on how to report security-related issues to us, please see the following webpage: https://www.citrix.com/about/trust-center/vulnerability-process.html 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. Cloud Software Group reserves the right to change or update this document at any time. Customers are therefore recommended to always view the latest version of this document directly from the Citrix Knowledge Center. Severity: High Description of Problem Several issues have been identified

Review the complete instructions on the vendor's site
Timeline

When this advisory changed

  1. Published by Citrix

    The publication date reported by the vendor.

  2. Added to SecurityAlert

    We collected the advisory from the official source.

Vulnerabilities

CVEs named in this advisory