CVE-2026-23556 (GCVE-0-2026-23556)
Vulnerability from cvelistv5 – Published: 2026-07-09 14:48 – Updated: 2026-07-09 15:37
VLAI
EPSS
VEX
Title
oxenstored keeps quota related use counts across domain destruction
Summary
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.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-09 15:34 UTC
CWE
- CWE-281 - Improper preservation of permissions
Assigner
References
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Xen | oxenstored |
Affected:
all
|
guessed |
{
"containers": {
"adp": [
{
"providerMetadata": {
"dateUpdated": "2026-07-09T15:06:25.267Z",
"orgId": "af854a3a-2127-422b-91ae-364da2661108",
"shortName": "CVE"
},
"references": [
{
"url": "http://www.openwall.com/lists/oss-security/2026/04/28/10"
},
{
"url": "http://xenbits.xen.org/xsa/advisory-483.html"
}
],
"title": "CVE Program Container"
},
{
"metrics": [
{
"other": {
"content": {
"id": "CVE-2026-23556",
"options": [
{
"Exploitation": "none"
},
{
"Automatable": "no"
},
{
"Technical Impact": "total"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-07-09T15:34:22.728700Z",
"version": "2.0.3"
},
"type": "ssvc"
}
}
],
"providerMetadata": {
"dateUpdated": "2026-07-09T15:37:46.026Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"title": "CISA ADP Vulnrichment"
}
],
"cna": {
"affected": [
{
"defaultStatus": "unaffected",
"product": "oxenstored",
"vendor": "Xen",
"versions": [
{
"status": "affected",
"version": "all"
}
]
}
],
"credits": [
{
"lang": "en",
"type": "finder",
"value": "This issue was discovered by Andrii Sultanov of Vates."
}
],
"descriptions": [
{
"lang": "en",
"supportingMedia": [
{
"base64": false,
"type": "text/html",
"value": "\u003cpre\u003eWhen oxenstored is tearing a domain down, the node data is cleaned up\nbut the usage counts are leaked.\n\nWhen the domain ID is eventually reused, the new domain can create fewer\nnodes before beeing deemed to be over quota.\u003c/pre\u003e"
}
],
"value": "When oxenstored is tearing a domain down, the node data is cleaned up\nbut the usage counts are leaked.\n\nWhen the domain ID is eventually reused, the new domain can create fewer\nnodes before beeing deemed to be over quota."
}
],
"impacts": [
{
"capecId": "CAPEC-548",
"descriptions": [
{
"lang": "en",
"value": "CAPEC-548 Contaminate Resource"
}
]
}
],
"metrics": [
{
"cvssV4_0": {
"Automatable": "NOT_DEFINED",
"Recovery": "NOT_DEFINED",
"Safety": "NOT_DEFINED",
"attackComplexity": "LOW",
"attackRequirements": "NONE",
"attackVector": "LOCAL",
"baseScore": 9.4,
"baseSeverity": "CRITICAL",
"exploitMaturity": "NOT_DEFINED",
"privilegesRequired": "NONE",
"providerUrgency": "NOT_DEFINED",
"subAvailabilityImpact": "HIGH",
"subConfidentialityImpact": "HIGH",
"subIntegrityImpact": "HIGH",
"userInteraction": "NONE",
"valueDensity": "NOT_DEFINED",
"vectorString": "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",
"version": "4.0",
"vulnAvailabilityImpact": "HIGH",
"vulnConfidentialityImpact": "HIGH",
"vulnIntegrityImpact": "HIGH",
"vulnerabilityResponseEffort": "NOT_DEFINED"
},
"format": "CVSS",
"scenarios": [
{
"lang": "en",
"value": "GENERAL"
}
]
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-281",
"description": "CWE-281 Improper preservation of permissions",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-07-09T14:48:56.630Z",
"orgId": "23aa2041-22e1-471f-9209-9b7396fa234f",
"shortName": "XEN"
},
"references": [
{
"url": "https://xenbits.xen.org/xsa/advisory-483.html"
}
],
"source": {
"discovery": "UNKNOWN"
},
"title": "oxenstored keeps quota related use counts across domain destruction",
"x_generator": {
"engine": "Vulnogram 1.0.2"
}
}
},
"cveMetadata": {
"assignerOrgId": "23aa2041-22e1-471f-9209-9b7396fa234f",
"assignerShortName": "XEN",
"cveId": "CVE-2026-23556",
"datePublished": "2026-07-09T14:48:56.630Z",
"dateReserved": "2026-01-14T13:07:36.961Z",
"dateUpdated": "2026-07-09T15:37:46.026Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"vulnerability-lookup:meta": {
"epss": {
"cve": "CVE-2026-23556",
"date": "2026-11-01",
"epss": "0.00137",
"percentile": "0.03074"
},
"nvd": {
"cve": {
"affected": [
{
"affectedData": [
{
"defaultStatus": "unaffected",
"product": "oxenstored",
"vendor": "Xen",
"versions": [
{
"status": "affected",
"version": "all"
}
]
}
],
"source": "security@xen.org"
}
],
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "When oxenstored is tearing a domain down, the node data is cleaned up\nbut the usage counts are leaked.\n\nWhen the domain ID is eventually reused, the new domain can create fewer\nnodes before beeing deemed to be over quota."
},
{
"lang": "es",
"value": "Cuando oxenstored est\u00e1 desmontando un dominio, los datos del nodo se limpian pero los recuentos de uso se filtran.\n\nCuando el ID del dominio se reutiliza finalmente, el nuevo dominio puede crear menos nodos antes de ser considerado que excede la cuota."
}
],
"id": "CVE-2026-23556",
"lastModified": "2026-10-25T17:10:00.197",
"metrics": {
"cvssMetricV40": [
{
"cvssData": {
"Automatable": "NOT_DEFINED",
"Recovery": "NOT_DEFINED",
"Safety": "NOT_DEFINED",
"attackComplexity": "LOW",
"attackRequirements": "NONE",
"attackVector": "LOCAL",
"availabilityRequirement": "NOT_DEFINED",
"baseScore": 9.4,
"baseSeverity": "CRITICAL",
"confidentialityRequirement": "NOT_DEFINED",
"exploitMaturity": "NOT_DEFINED",
"integrityRequirement": "NOT_DEFINED",
"modifiedAttackComplexity": "NOT_DEFINED",
"modifiedAttackRequirements": "NOT_DEFINED",
"modifiedAttackVector": "NOT_DEFINED",
"modifiedPrivilegesRequired": "NOT_DEFINED",
"modifiedSubAvailabilityImpact": "NOT_DEFINED",
"modifiedSubConfidentialityImpact": "NOT_DEFINED",
"modifiedSubIntegrityImpact": "NOT_DEFINED",
"modifiedUserInteraction": "NOT_DEFINED",
"modifiedVulnAvailabilityImpact": "NOT_DEFINED",
"modifiedVulnConfidentialityImpact": "NOT_DEFINED",
"modifiedVulnIntegrityImpact": "NOT_DEFINED",
"privilegesRequired": "NONE",
"providerUrgency": "NOT_DEFINED",
"subAvailabilityImpact": "HIGH",
"subConfidentialityImpact": "HIGH",
"subIntegrityImpact": "HIGH",
"userInteraction": "NONE",
"valueDensity": "NOT_DEFINED",
"vectorString": "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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
"version": "4.0",
"vulnAvailabilityImpact": "HIGH",
"vulnConfidentialityImpact": "HIGH",
"vulnIntegrityImpact": "HIGH",
"vulnerabilityResponseEffort": "NOT_DEFINED"
},
"source": "security@xen.org",
"type": "Secondary"
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2026-23556",
"options": [
{
"exploitation": "none"
},
{
"automatable": "no"
},
{
"technicalImpact": "total"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-07-09T15:34:22.728700Z",
"version": "2.0.3"
}
}
]
},
"published": "2026-07-09T16:16:38.690",
"references": [
{
"source": "security@xen.org",
"url": "https://xenbits.xen.org/xsa/advisory-483.html"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"url": "http://www.openwall.com/lists/oss-security/2026/04/28/10"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"url": "http://xenbits.xen.org/xsa/advisory-483.html"
}
],
"sourceIdentifier": "security@xen.org",
"vulnStatus": "Deferred",
"weaknesses": [
{
"description": [
{
"lang": "en",
"value": "CWE-281"
}
],
"source": "security@xen.org",
"type": "Secondary"
}
]
}
},
"vulnrichment": {
"containers": {
"adp": [
{
"providerMetadata": {
"dateUpdated": "2026-07-09T15:06:25.267Z",
"orgId": "af854a3a-2127-422b-91ae-364da2661108",
"shortName": "CVE"
},
"references": [
{
"url": "http://www.openwall.com/lists/oss-security/2026/04/28/10"
},
{
"url": "http://xenbits.xen.org/xsa/advisory-483.html"
}
],
"title": "CVE Program Container"
},
{
"metrics": [
{
"other": {
"content": {
"id": "CVE-2026-23556",
"options": [
{
"Exploitation": "none"
},
{
"Automatable": "no"
},
{
"Technical Impact": "total"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-07-09T15:34:22.728700Z",
"version": "2.0.3"
},
"type": "ssvc"
}
}
],
"providerMetadata": {
"dateUpdated": "2026-07-09T15:37:42.454Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"title": "CISA ADP Vulnrichment"
}
],
"cna": {
"affected": [
{
"defaultStatus": "unaffected",
"product": "oxenstored",
"vendor": "Xen",
"versions": [
{
"status": "affected",
"version": "all"
}
]
}
],
"credits": [
{
"lang": "en",
"type": "finder",
"value": "This issue was discovered by Andrii Sultanov of Vates."
}
],
"descriptions": [
{
"lang": "en",
"supportingMedia": [
{
"base64": false,
"type": "text/html",
"value": "\u003cpre\u003eWhen oxenstored is tearing a domain down, the node data is cleaned up\nbut the usage counts are leaked.\n\nWhen the domain ID is eventually reused, the new domain can create fewer\nnodes before beeing deemed to be over quota.\u003c/pre\u003e"
}
],
"value": "When oxenstored is tearing a domain down, the node data is cleaned up\nbut the usage counts are leaked.\n\nWhen the domain ID is eventually reused, the new domain can create fewer\nnodes before beeing deemed to be over quota."
}
],
"impacts": [
{
"capecId": "CAPEC-548",
"descriptions": [
{
"lang": "en",
"value": "CAPEC-548 Contaminate Resource"
}
]
}
],
"metrics": [
{
"cvssV4_0": {
"Automatable": "NOT_DEFINED",
"Recovery": "NOT_DEFINED",
"Safety": "NOT_DEFINED",
"attackComplexity": "LOW",
"attackRequirements": "NONE",
"attackVector": "LOCAL",
"baseScore": 9.4,
"baseSeverity": "CRITICAL",
"exploitMaturity": "NOT_DEFINED",
"privilegesRequired": "NONE",
"providerUrgency": "NOT_DEFINED",
"subAvailabilityImpact": "HIGH",
"subConfidentialityImpact": "HIGH",
"subIntegrityImpact": "HIGH",
"userInteraction": "NONE",
"valueDensity": "NOT_DEFINED",
"vectorString": "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",
"version": "4.0",
"vulnAvailabilityImpact": "HIGH",
"vulnConfidentialityImpact": "HIGH",
"vulnIntegrityImpact": "HIGH",
"vulnerabilityResponseEffort": "NOT_DEFINED"
},
"format": "CVSS",
"scenarios": [
{
"lang": "en",
"value": "GENERAL"
}
]
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-281",
"description": "CWE-281 Improper preservation of permissions",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-07-09T14:48:56.630Z",
"orgId": "23aa2041-22e1-471f-9209-9b7396fa234f",
"shortName": "XEN"
},
"references": [
{
"url": "https://xenbits.xen.org/xsa/advisory-483.html"
}
],
"source": {
"discovery": "UNKNOWN"
},
"title": "oxenstored keeps quota related use counts across domain destruction",
"x_generator": {
"engine": "Vulnogram 1.0.2"
}
}
},
"cveMetadata": {
"assignerOrgId": "23aa2041-22e1-471f-9209-9b7396fa234f",
"assignerShortName": "XEN",
"cveId": "CVE-2026-23556",
"datePublished": "2026-07-09T14:48:56.630Z",
"dateReserved": "2026-01-14T13:07:36.961Z",
"dateUpdated": "2026-07-09T15:37:46.026Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}
}
}
Loading…
Loading…
Drag nodes to arrange them. Double-click a related vulnerability to open it, or a source to visit its link. The Physics button on the left tunes the layout and the simulation; the legend at the bottom left hides or shows nodes by kind and by sighting type.
Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
Vulnerability timeline
Sightings and recorded dates, grouped by day · UTC
Loading timeline…
Loading…
Loading…
The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
Loading…
Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.