What is CVE-2026-42487?

CVE-2026-42487 is a high-severity vulnerability in Xen, classified under Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition). CVSS score: 7.9/10. Published 2026-06-18.

How severe is CVE-2026-42487?

High severity. CVSS v3 base score is 7.9 out of 10.

Vulnerability in Xen

CVE-2026-42487

HVM guest I/O port accesses are subject to either emulation or at least translation. Translations are managed by the device model (via XEN_DOMCTL_ioport_mapping), and hence the linked list used may changed at any time. Traversal of those…

Vulnerability class: Race Condition

CVSS v3 metric

CVSS v3 base score 7.9 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:H.

Affected products

Xen — versions consult Xen advisory XSA-491

Weakness classification (CWE)

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

References

security@xen.org
af854a3a-2127-422b-91ae-364da2661108
af854a3a-2127-422b-91ae-364da2661108

Frequently asked questions

What is CVE-2026-42487?: CVE-2026-42487 is a high-severity vulnerability in Xen, classified under Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition). CVSS score: 7.9/10. Published 2026-06-18.
How severe is CVE-2026-42487?: High severity. CVSS v3 base score is 7.9 out of 10.