CVE-2026-62431 - Vulnerability Details - OpenCVE

Description

The logic to handle periodic Viridian STIMERs performs a division with an
unchecked user-controlled divisor value, that can be set to zero to cause a #DE
fault.

Published: 2026-07-28

Score: 7.5 High

EPSS: n/a

KEV: No

Impact:

Action:

Analysis

Analysis and contextual insights are available on OpenCVE Cloud.

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

Xen

Xen

unknown

Version	Status	Constraints
`consult Xen advisory XSA-504`	unknown	—

No data.

No data.

No data available yet.

Remediation

Vendor Workaround

Not enabling Viridian STIMERs for HVM guests will avoid the vulnerability. Note Viridian extensions are not enabled by default.

Tracking

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Advisories

No advisories yet.

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Exploitation none

Automatable yes

Technical Impact partial

References

Link	Providers
https://xenbits.xenproject.org/xsa/advisory-504.html

History

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

Type	Values Removed	Values Added
Description		The logic to handle periodic Viridian STIMERs performs a division with an unchecked user-controlled divisor value, that can be set to zero to cause a #DE fault.
Title		Viridian STIMER division by zero
Weaknesses		CWE-369
References		https://xenbits.xenproject.org/xsa/advisory-504.html
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'}`

Subscriptions

No data.

MITRE

Status: PUBLISHED

Assigner: XEN

Published: 2026-07-28T12:32:43.849Z

Updated: 2026-07-28T16:33:31.447Z

Reserved: 2026-07-14T10:28:12.655Z

Link: CVE-2026-62431

Vulnrichment

Updated: 2026-07-28T16:33:31.447Z

NVD

No data.

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

CWE-369

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