CVE-2026-23556 - Vulnerability Details - OpenCVE

When oxenstored is tearing a domain down, the node data is cleaned up but the usage counts are leaked. When the domain ID is eventually reused, the new domain can create fewer nodes before beeing deemed to be over quota.

Attack Vector Local

Attack Complexity Low

Privileges Required None

Attack Requirements None

User Interaction None

Vulnerable System Confidentiality Impact High

Vulnerable System Integrity Impact High

Vulnerable System Availability Impact High

Subsequent System Confidentiality Impact High

Subsequent System Integrity Impact High

Subsequent System Availability Impact High

No CVSS v3.1

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Exploitation none

Automatable no

Technical Impact total

Vendors	Products
Xen	Oxenstored

No data.

No data.

References

Link	Providers
https://xenbits.xen.org/xsa/advisory-483.html

History

Fri, 10 Jul 2026 10:15:00 +0000

Type	Values Removed	Values Added
First Time appeared		Xen Xen oxenstored
Vendors & Products		Xen Xen oxenstored

Thu, 09 Jul 2026 17:30:00 +0000

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}`

Thu, 09 Jul 2026 15:45:00 +0000

Type	Values Removed	Values Added
Description		When oxenstored is tearing a domain down, the node data is cleaned up but the usage counts are leaked. When the domain ID is eventually reused, the new domain can create fewer nodes before beeing deemed to be over quota.
Title		oxenstored keeps quota related use counts across domain destruction
Weaknesses		CWE-281
References		https://xenbits.xen.org/xsa/advisory-483.html
Metrics		cvssV4_0 `{'score': 9.4, 'vector': 'CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H'}`

MITRE

Status: PUBLISHED

Assigner: XEN

Published: 2026-07-09T14:48:56.630Z

Updated: 2026-07-09T15:37:46.026Z

Reserved: 2026-01-14T13:07:36.961Z

Link: CVE-2026-23556

Vulnrichment

Updated: 2026-07-09T15:06:25.267Z

NVD

No data.

Redhat

No data.

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