CVE-2026-42487 — x86 HVM I/O port list traversal

Description (CNA)

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.

Affected (CNA)

Vendor / product	Versions
Xen / Xen	unknown consult Xen advisory XSA-491

CWE

No CWE identifiers supplied.

References

https://xenbits.xenproject.org/xsa/advisory-491.html

ADP enrichment

CISA-ADP

No English description supplied.

No references supplied.

CVE

No English description supplied.

http://xenbits.xen.org/xsa/advisory-491.html
http://www.openwall.com/lists/oss-security/2026/06/09/11