Xenstore, to have an up-to-date picture of the entire system, wants to know of domains appearing and disappearing. To make this more robust, a new XEN_DOMCTL_get_domain_state was introduced. The management of the bitmap underlying that operation is tied into the binding of the VIRQ_DOM_EXC virtual IRQ. Unfortunately an error path there would tear down the bitmap even in cases when it wasn't set up. Unprivileged domains can trigger that error path.
History

Tue, 28 Jul 2026 19:15:00 +0000

Type Values Removed Values Added
First Time appeared Xen
Xen xen
Vendors & Products Xen
Xen xen

Tue, 28 Jul 2026 16:15:00 +0000

Type Values Removed Values Added
Description Xenstore, to have an up-to-date picture of the entire system, wants to know of domains appearing and disappearing. To make this more robust, a new XEN_DOMCTL_get_domain_state was introduced. The management of the bitmap underlying that operation is tied into the binding of the VIRQ_DOM_EXC virtual IRQ. Unfortunately an error path there would tear down the bitmap even in cases when it wasn't set up. Unprivileged domains can trigger that error path.
Title vIRQ event channel binding may break Xenstore
Weaknesses CWE-459
References
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}

ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


cve-icon MITRE

Status: PUBLISHED

Assigner: XEN

Published:

Updated: 2026-07-28T16:33:22.683Z

Reserved: 2026-04-27T14:20:24.139Z

Link: CVE-2026-42492

cve-icon Vulnrichment

Updated: 2026-07-28T16:33:22.683Z

cve-icon NVD

No data.

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-07-28T19:00:04Z