CVE-2026-23558

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 3.1

7.8CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H

EPSS

0.1% chance of exploitation in the next 30 days; higher than 1% of CVEs (scores of 2026-10-25)

CWE

CWE-362

Published

2026-05-19

Modified

2026-10-14

Record from

the NVD, synced 2026-10-19

Affected

• xen:xen

References

• https://xenbits.xenproject.org/xsa/advisory-486.html
• http://www.openwall.com/lists/oss-security/2026/04/28/13
• http://xenbits.xen.org/xsa/advisory-486.html

Check your stackJSON