Name: CVE-2026-23558: Concurrent Execution using Shared Resource with Improper Synchronization
Creator: Rapid7
Published: 2026-05-19T00:00:00.000Z
License: https://www.rapid7.com/legal/website-terms-of-use/
Keywords: CVE, CVE-2026-23558, CWE-362, CVSS 7.8, EPSS 0.00117

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.

CVSS Details

CVSS 3.1 Base Score: 7.8
CVSS 3.1 Vector: (CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H)

Covered by Rapid7

Product	Vendor Advisory	Solution File	Added	Published
Alpine Linux	—	Upgrade xen	May 20, 2026	May 19, 2026
Debian	—	Upgrade xen	Aug 11, 2026	May 19, 2026

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CVSS Details

Covered by Rapid7

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