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

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.

Published: 2026-06-18 Last update: 2026-06-18 Assigner: [email protected] Source: [email protected]
NVD Status：Received，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-42487 is rated Moderate Risk (48.6/100): CVSS High severity. Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-42487

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

EPSS has not published a score for this CVE yet—common while NVD analysis or FIRST scoring is still pending. Monitor daily updates and reassess once scores appear.

Common vulnerability scoring system (CVSS) metrics for CVE-2026-42487

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.9 3.1 HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 2.0 5.3 134c704f-9b21-4f2e-91b3-4a467353bcc0

Weakness enumeration for CVE-2026-42487

GitHub Security Advisory for CVE-2026-42487

GHSA-xx8x-hq3h-f37h · Severity: high — HVM guest I/O port accesses are subject to either emulation or at least translation. ...

OS Trackers for CVE-2026-42487

vendor priority summary link
debian end-of-life CVE-2026-42487 end-of-life priority: Debian including 1 source packages (xen), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): open 5. https://security-tracker.debian.org/tracker/CVE-2026-42487
suse high CVE-2026-42487 severity important: SUSE including 18 source package names (xen-4.17.6_12-150500.3.73.1, xen-4.18.5_18-150600.3.50.1, …), 43 product×package rows across 9 product lines (SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS, SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS, … (9 product lines)): Fixed 43. https://www.suse.com/security/cve/CVE-2026-42487/
ubuntu medium CVE-2026-42487 medium priority: Ubuntu including 1 source packages (xen), 8 status rows across 8 suites (bionic, focal, jammy, noble, questing, resolute, upstream, xenial): needs-triage 8. https://ubuntu.com/security/CVE-2026-42487

Affected software / configurations for CVE-2026-42487

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2026-42487

cvelogic Threat Intelligence