CVE-2026-23558

Severity CVSS v4.0:

Pending analysis

Type:

CWE-362 Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

Publication date:

19/05/2026

Last modified:

19/05/2026

Description

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&#39;s secondary (P2M) page tables.

Impact

Vector 3.x

CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H CVSS v3.1 Severity and Metrics:

Base Score: 7.80 HIGH
Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H

Attack Vector (AV): Local
Attack Complexity (AC): High
Privileges Required (PR): Low
User Interaction (UI): None
Scope (S): Changed
Confidentiality (C): High
Integrity (I): High
Availability (A): High