CVE-2026-23558: grant table v2 race in status page mapping
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.
Affected Software
Remediation
Patch Available
Patch Available
Patch Available
Event History
Frequently Asked Questions
What is the severity of CVE-2026-23558?
CVE-2026-23558 has a severity rating of high, with a CVSS score of 7.8.
How do I fix CVE-2026-23558?
To fix CVE-2026-23558, apply the available patch provided in the official advisory.
What type of vulnerability is CVE-2026-23558?
CVE-2026-23558 is categorized as a race condition vulnerability affecting the Xen Hypervisor.
What systems are affected by CVE-2026-23558?
CVE-2026-23558 affects the XEN Xen Hypervisor and may impact HVM or PVH guests.
What is the nature of the risk associated with CVE-2026-23558?
The risk associated with CVE-2026-23558 involves potential memory corruption due to a race condition during grant table management.