VulnerabilityDeferred

CVE-2026-42487

Traversal of those lists (while handling guest I/O port accesses) therefore needs synchronizing with updates, which was missing so far.

HIGH 7.9EPSS 0.10%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.10%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

HVM guest I/O port accesses are subject to either emulation or at least translation. Translations are managed by the device model (via XEN_DOMCTL_ioport_mapping), and hence the linked list used may changed at any time. Traversal of those lists (while handling guest I/O port accesses) therefore needs synchronizing with updates, which was missing so far.

CVSS 3.1: 7.9 HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:H
EPSS: 0.10% probability · 1th percentile
CISA KEV: Not listed
Weakness: CWE-362
Source: security@xen.org

References

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