Concurrency Vulnerability in Xen Domctl Operations Affecting Xen Project
CVE-2026-42489

5.3MEDIUM

Key Information:

Vendor

Xen Project
Status
Xen Project
Vendor
CVE Published:
18 June 2026

What is CVE-2026-42489?

The Xen Project's domctl operations, utilized for creating and managing guests, exhibit a concurrency vulnerability due to improper lock acquisition, lacking fairness in resource access. This flaw allows the system-wide lock to be obtained in a manner that does not prioritize fairness among operations, potentially leading to inconsistent access patterns and resource management issues. Additionally, in configurations where XSM/Flask is utilized, the lock acquisition precedes permission checks for certain operations, further compounding the security risk.

Affected Version(s)

Xen consult Xen advisory XSA-492

References

https://xenbits.xenproject.org/xsa/advisory-492.html

CVSS V3.1

Score:
5.3
Severity:
MEDIUM
Confidentiality:
None
Integrity:
None
Availability:
None
Attack Vector:
Local
Attack Complexity:
High
Privileges Required:
High
User Interaction:
None
Scope:
Changed

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

This issue was discovered by Andrew Cooper of Citrix.
.