Description
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.
References3
Metrics
- CVSS 3.1
-
4.3
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N - EPSS — exploit probability
- 0% percentile: 13 · as of 3 November 2026
- CWE
- CWE-664
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