CVE-2026-79603: Xen

Medium severity, CVSS 4.3. EPSS: 0.2% chance of exploitation in the next 30 days.

x86 PV guests can free memory pages while still keeping a stale TLB entry pointing to them. A TLB flush is only issued by Xen (if needed) when the page is re-used. Since it's possible for the page to be scrubbed ahead of the TLB flush, there's a window where a PV guest can modify an already scrubbed page.

Affected products

Published 2026-09-08. Last modified 2026-09-08.