Vulnerability in Xen

CVE-2026-62427

[This CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] To manage the system, sysctl and platform operations are used by the control domain or a possible Xenstore domain. Some of these operations may not be executed in parallel, so a system-wide lock each is used. The way those locks are acquired is, however, not providing any fairness. Furthermore, with XSM/Flask in use, the lock acquire will, for some operations, occur ahead of any permission checking. The sysctl issue is CVE-2026-62426. The platform-op issue is CVE-2026-62427.

EPSS: 0.002 (15.1th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Affected products

  • Xen — versions consult Xen advisory XSA-499

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-62427?
CVE-2026-62427 is a high-severity vulnerability in Xen, classified under Improper Access Control. CVSS score: 8.8/10. Published 2026-07-28.
How severe is CVE-2026-62427?
High severity. CVSS v3 base score is 8.8 out of 10.