[ CVE-2026-79609 · Published 13 Oct 2026 ]
Vulnerability in Xen
[ Description ]Official description
XPTI (Xen Page Table Isolation) was introduced to mitigate Meltdown (CVE-2017-5754, one aspect of XSA-254). This involves copying 64-bit PV guest page table entries from guest-chosen root page tables to the Xen- chosen one which is in actual use by hardware. To read the guest root page table, the directmap is used. PV guests, however, have a directmap which may not cover all memory; in particular this is the case if any memory extends beyond the 5 TiB (CONFIG_BIGMEM=y: 3.5 TiB) address boundary.
[ Fixes ]Fixes and patches
No fix or interim patch is linked from our sources yet. Check the vendor references below and limit exposure of affected systems until a fix is available.
[ Advisories ]Government CERT advisories
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CERT-FRCERTFR-2026-AVI-1302
Multiple vulnerabilities in Xen Translated from French
Multiple vulnerabilities have been discovered in Xen. Some of them allow an attacker to cause arbitrary code execution, privilege escalation and a breach of data confidentiality.
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BSI CERT-BundWID-SEC-2026-3930
Xen: Multiple vulnerabilities Translated from German