PT-2026-26014 · Intel+1 · Intel Ept+1

Roger Pau · Published 2026-01-01 · Updated 2026-03-28 · CVE-2026-23554

Positive Technologies (AI Summary)

CVSS v3.1

7.8

High

Base vector

AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H

Name of the Vulnerable Software and Affected Versions Citrix XenServer version 8.4

Description The Intel EPT paging code includes an optimization that defers flushing of cached EPT state until the p2m lock is released. However, the freeing of paging structures is not deferred, potentially leading to stale entries pointing to memory regions not owned by the guest. This can allow access to unintended memory regions. The issue may allow privileged code in a guest virtual machine to compromise the host system.

Recommendations Update XenServer version 8.4 to the latest firmware or software. Verify all XenServer 8.4 hosts are patched.

Fix

Time Of Check To Time Of Use

Weakness Enumeration

CWE-367

Related Identifiers

CVE-2026-23554

MGASA-2026-0068

OPENSUSE-SU-2026:10457-1

SUSE-SU-2026:0908-1

SUSE-SU-2026:1092-1

SUSE-SU-2026:1093-1

Affected Products

Citrix Xenserver 8.4

Intel Ept

References · 33

• https://security-tracker.debian.org/tracker/CVE-2026-23554 · Vendor Advisory
• https://ubuntu.com/security/CVE-2026-23554 · Vendor Advisory
• https://osv.dev/vulnerability/DEBIAN-CVE-2026-23554 · Vendor Advisory
• https://advisories.mageia.org/MGASA-2026-0068.html · Security Note
• https://xenbits.xenproject.org/xsa/advisory-480.html · Vendor Advisory
• https://osv.dev/vulnerability/MGASA-2026-0068 · Vendor Advisory
• https://osv.dev/vulnerability/SUSE-SU-2026:0908-1 · Vendor Advisory
• http://xenbits.xen.org/xsa/advisory-480.html · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-23554 · Security Note
• https://osv.dev/vulnerability/UBUNTU-CVE-2026-23554 · Vendor Advisory
• https://osv.dev/vulnerability/openSUSE-SU-2026:10457-1 · Vendor Advisory
• https://osv.dev/vulnerability/ALPINE-CVE-2026-23554 · Vendor Advisory
• https://osv.dev/vulnerability/SUSE-SU-2026:1093-1 · Vendor Advisory
• https://cve.org/CVERecord?id=CVE-2026-23554 · Security Note
• https://osv.dev/vulnerability/SUSE-SU-2026:1092-1 · Vendor Advisory