CVE-2018-19965: Citrix Xenserver

Medium severity, CVSS 5.6. EPSS: 0.4% chance of exploitation in the next 30 days.

An issue was discovered in Xen through 4.11.x allowing 64-bit PV guest OS users to cause a denial of service (host OS crash) because #GP[0] can occur after a non-canonical address is passed to the TLB flushing code. NOTE: this issue exists because of an incorrect CVE-2017-5754 (aka Meltdown) mitigation.

Affected products

• Citrix Xenserver: version 7.0 only; version 7.1 only; version 7.5 only; version 7.6 only
• Debian Debian Linux: version 9.0 only
• Xen Xen: up to and including 4.11.1

Published 2018-12-08. Last modified 2026-06-17.