CVE-2026-62427 (GCVE-0-2026-62427)

Vulnerability from cvelistv5 – Published: 2026-07-28 12:31 – Updated: 2026-07-28 15:54
VLAI
Title
sysctl and platform-op locks open to abuse
Summary
[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.
Severity
8.8 (High)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-28 15:54 UTC
CWE
  • CWE-284 - Improper Access Control
  • CWE-305 - Authentication Bypass by Primary Weakness
Assigner
XEN CNA under the mitre root
CNA scorecard D 56/100 over 46 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Xen Xen Unknown: consult Xen advisory XSA-499
guessed Create a notification for this product.
Date Public
2026-07-28 12:00
Credits
This issue was discovered by Jan Beulich of SUSE.
Show details on NVD website
To clipboard 

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