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CVE-2026-23558 (GCVE-0-2026-23558)

Vulnerability from cvelistv5 – Published: 2026-05-19 12:49 – Updated: 2026-05-20 03:55
VLAI
Title
grant table v2 race in status page mapping
Summary
The adjustments made for XSA-379 as well as those subsequently becoming XSA-387 still left a race window, when a HVM or PVH guest does a grant table version change from v2 to v1 in parallel with mapping the status page(s) via XENMEM_add_to_physmap. Some of the status pages may then be freed while mappings of them would still be inserted into the guest's secondary (P2M) page tables.
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 2026-05-19 00:00 UTC
CWE
  • CWE-362 - Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')
Assigner
References
Impacted products
Vendor Product Version CPE status
Xen Xen Unknown: consult Xen advisory XSA-486
guessed Create a notification for this product.
Date Public
2026-04-28 12:00
Credits
This issue was discovered by Claude Opus 4.6 and diagnosed as a security issue by Rafal Wojtczuk.
Show details on NVD website
To clipboard 

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  • 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 confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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