CVE-2026-58214
Full vulnerability record from the local CVENow database.
Description
NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.14.3 and 2.12.12, an authenticated MQTT client could subscribe to the internal $MQTT.deliver.pubrel subject family, bypassing configured subscribe permissions and exposing MQTT QoS2 protocol metadata for sessions in the account. This issue is fixed in versions 2.14.3 and 2.12.12.
Severity
MEDIUM
CVSS score
4.3
(v3.1)
Vulnerability status
Analyzed
Source identifier
Published
2026-07-08 20:16:54.347000
Last modified
2026-10-25 17:10:00.197000
View original CVE JSON
{
"id": "CVE-2026-58214",
"sourceIdentifier": "[email protected]",
"published": "2026-07-08T20:16:54.347",
"lastModified": "2026-10-25T17:10:00.197",
"vulnStatus": "Analyzed",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.14.3 and 2.12.12, an authenticated MQTT client could subscribe to the internal $MQTT.deliver.pubrel subject family, bypassing configured subscribe permissions and exposing MQTT QoS2 protocol metadata for sessions in the account. This issue is fixed in versions 2.14.3 and 2.12.12."
},
{
"lang": "es",
"value": "NATS Server es un servidor de alto rendimiento para NATS.io, el sistema de mensajería nativo de la nube y del borde. Antes de las versiones 2.14.3 y 2.12.12, un cliente MQTT autenticado podía suscribirse a la familia de asuntos internos $MQTT.deliver.pubrel, eludiendo los permisos de suscripción configurados y exponiendo metadatos del protocolo MQTT QoS2 para sesiones en la cuenta. Este problema está solucionado en las versiones 2.14.3 y 2.12.12."
}
],
"affected": [
{
"source": "[email protected]",
"affectedData": [
{
"vendor": "nats-io",
"product": "nats-server",
"versions": [
{
"version": "< 2.12.12",
"status": "affected"
},
{
"version": ">= 2.14.0-RC.1, < 2.14.3",
"status": "affected"
}
]
}
]
}
],
"metrics": {
"cvssMetricV31": [
{
"source": "[email protected]",
"type": "Secondary",
"cvssData": {
"version": "3.1",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N",
"baseScore": 4.3,
"baseSeverity": "MEDIUM",
"attackVector": "NETWORK",
"attackComplexity": "LOW",
"privilegesRequired": "LOW",
"userInteraction": "NONE",
"scope": "UNCHANGED",
"confidentialityImpact": "LOW",
"integrityImpact": "NONE",
"availabilityImpact": "NONE"
},
"exploitabilityScore": 2.8,
"impactScore": 1.4
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"timestamp": "2026-07-09T13:32:18.907165Z",
"id": "CVE-2026-58214",
"options": [
{
"exploitation": "none"
},
{
"automatable": "no"
},
{
"technicalImpact": "partial"
}
],
"role": "CISA Coordinator",
"version": "2.0.3"
}
}
]
},
"weaknesses": [
{
"source": "[email protected]",
"type": "Secondary",
"description": [
{
"lang": "en",
"value": "CWE-863"
}
]
}
],
"configurations": [
{
"nodes": [
{
"operator": "OR",
"negate": false,
"cpeMatch": [
{
"vulnerable": true,
"criteria": "cpe:2.3:a:linuxfoundation:nats-server:*:*:*:*:*:*:*:*",
"versionEndExcluding": "2.12.12",
"matchCriteriaId": "3662387F-C5A6-478A-94D1-849E3C7E81DB"
},
{
"vulnerable": true,
"criteria": "cpe:2.3:a:linuxfoundation:nats-server:*:*:*:*:*:*:*:*",
"versionStartIncluding": "2.14.0",
"versionEndExcluding": "2.14.3",
"matchCriteriaId": "9BF70729-64AF-4219-BC35-3C5C042F0595"
}
]
}
]
}
],
"references": [
{
"url": "https://github.com/nats-io/nats-server/commit/297b166be60fe13144084eed4b25201ead03204a",
"source": "[email protected]",
"tags": [
"Patch"
]
},
{
"url": "https://github.com/nats-io/nats-server/commit/34b09657bb596d5f850eaa5cfc97ea6b2f989a97",
"source": "[email protected]",
"tags": [
"Patch"
]
},
{
"url": "https://github.com/nats-io/nats-server/releases/tag/v2.12.12",
"source": "[email protected]",
"tags": [
"Release Notes"
]
},
{
"url": "https://github.com/nats-io/nats-server/releases/tag/v2.14.3",
"source": "[email protected]",
"tags": [
"Release Notes"
]
},
{
"url": "https://github.com/nats-io/nats-server/security/advisories/GHSA-4g68-3pwx-5vfj",
"source": "[email protected]",
"tags": [
"Vendor Advisory"
]
}
]
}