CVE-2026-23554 (GCVE-0-2026-23554)

Vulnerability from cvelistv5 – Published: 2026-03-23 06:56 – Updated: 2026-03-23 14:19
VLAI
Title
Use after free of paging structures in EPT
Summary
The Intel EPT paging code uses an optimization to defer flushing of any cached EPT state until the p2m lock is dropped, so that multiple modifications done under the same locked region only issue a single flush. Freeing of paging structures however is not deferred until the flushing is done, and can result in freed pages transiently being present in cached state. Such stale entries can point to memory ranges not owned by the guest, thus allowing access to unintended memory regions.
Severity
7.8 (High)
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-23 14:18 UTC
CWE
  • CWE-367 - Time-of-check Time-of-use (TOCTOU) Race Condition
Assigner
References
Impacted products
Vendor Product Version CPE status
Xen Xen Unknown: consult Xen advisory XSA-480
guessed Create a notification for this product.
Date Public
2026-03-17 12:00
Credits
This issue was discovered by Roger Pau Monné of XenServer.
Show details on NVD website
To clipboard 

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}



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