CVE-2026-23558

High

Published: 19/05/2026(UTC)Translated: 15/06/2026(UTC)NVD NIST

Summary

CVE-2026-23558 describes a race condition that occurs during the grant table version change from v2 to v1 in HVM or PVH guests. This issue may lead to some status pages being freed while their mappings are still being inserted into the guest's page tables.

Risk Assessment

Organizations may face memory integrity issues and potential data leaks, which could lead to unauthorized access to system resources.

Recommendation

It is recommended to monitor and update systems to mitigate this vulnerability, as well as to implement additional security mechanisms to prevent unauthorized memory access.

Original NVD description (English source)

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.