VulnerabilityDeferred

CVE-2026-42492

Xenstore, to have an up-to-date picture of the entire system, wants to know of domains appearing and disappearing.

HIGH 7.5EPSS 0.46%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.46%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

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.

CVSS 3.1: 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS: 0.46% probability · 39th percentile
CISA KEV: Not listed
Weakness: CWE-459
Source: security@xen.org

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.