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CVE-2026-79603 (GCVE-0-2026-79603)

Vulnerability from cvelistv5 – Published: 2026-09-08 12:11 – Updated: 2026-09-08 17:08
VLAI
Title
Unconditionally do TLB flushing ahead of page scrubbing
Summary
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.
Severity
4.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-08 13:42 UTC
CWE
  • CWE-664 - Improper Control of a Resource Through its Lifetime
Assigner
References
Impacted products
Vendor Product Version CPE status
Xen Xen Unknown: consult Xen advisory XSA-511
guessed Create a notification for this product.
Date Public
2026-09-08 12:00
Credits
This issue was discovered by Roger Pau Monné of AMD.
Show details on NVD website
To clipboard 

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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