FKIE_CVE-2026-44327
Vulnerability from fkie_nvd - Published: 2026-05-27 17:16 - Updated: 2026-10-14 20:10
Severity
Summary
free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's NEF mounts the nnef-oam route group without inbound OAuth2/bearer-token authorization. A network attacker who can reach NEF on the SBI can hit the OAM route with no Authorization header at all and the handler returns 200 OK. The current OAM handler is a stub that returns null, but the structural defect is route-group-scoped: the entire OAM route group has no inbound auth middleware, so every future OAM operation added to this group inherits the missing auth boundary by default. This vulnerability is fixed in 4.2.2.
References
| URL | Tags | ||
|---|---|---|---|
| security-advisories@github.com | https://github.com/free5gc/free5gc/issues/861 | Exploit, Issue Tracking | |
| security-advisories@github.com | https://github.com/free5gc/free5gc/security/advisories/GHSA-cmpj-2x3g-m7g3 | Exploit, Vendor Advisory | |
| security-advisories@github.com | https://github.com/free5gc/nef/pull/23 | Issue Tracking, Patch | |
| 134c704f-9b21-4f2e-91b3-4a467353bcc0 | https://github.com/free5gc/free5gc/security/advisories/GHSA-cmpj-2x3g-m7g3 | Exploit, Vendor Advisory |
{
"affected": [
{
"affectedData": [
{
"product": "free5gc",
"vendor": "free5gc",
"versions": [
{
"status": "affected",
"version": "\u003c 4.2.2"
}
]
}
],
"source": "security-advisories@github.com"
}
],
"configurations": [
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:a:free5gc:free5gc:*:*:*:*:*:*:*:*",
"matchCriteriaId": "EF7EBB95-EB4E-44C5-BF0A-9C99B0A7775F",
"versionEndExcluding": "4.2.2",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC\u0027s NEF mounts the nnef-oam route group without inbound OAuth2/bearer-token authorization. A network attacker who can reach NEF on the SBI can hit the OAM route with no Authorization header at all and the handler returns 200 OK. The current OAM handler is a stub that returns null, but the structural defect is route-group-scoped: the entire OAM route group has no inbound auth middleware, so every future OAM operation added to this group inherits the missing auth boundary by default. This vulnerability is fixed in 4.2.2."
},
{
"lang": "es",
"value": "free5GC es una implementaci\u00f3n de c\u00f3digo abierto de la red central 5G. Antes de la versi\u00f3n 4.2.2, el NEF de free5GC monta el grupo de rutas nnef-oam sin autorizaci\u00f3n de entrada OAuth2/token de portador. Un atacante de red que puede alcanzar el NEF en la SBI puede acceder a la ruta OAM sin ning\u00fan encabezado de autorizaci\u00f3n y el gestor devuelve 200 OK. El gestor OAM actual es un stub que devuelve nulo, pero el defecto estructural est\u00e1 limitado al grupo de rutas: todo el grupo de rutas OAM no tiene middleware de autenticaci\u00f3n de entrada, por lo que cada futura operaci\u00f3n OAM a\u00f1adida a este grupo hereda el l\u00edmite de autenticaci\u00f3n faltante por defecto. Esta vulnerabilidad se corrige en la versi\u00f3n 4.2.2."
}
],
"id": "CVE-2026-44327",
"lastModified": "2026-10-14T20:10:00.190",
"metrics": {
"cvssMetricV31": [
{
"cvssData": {
"attackComplexity": "LOW",
"attackVector": "NETWORK",
"availabilityImpact": "HIGH",
"baseScore": 10.0,
"baseSeverity": "CRITICAL",
"confidentialityImpact": "LOW",
"integrityImpact": "HIGH",
"privilegesRequired": "NONE",
"scope": "CHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:H/A:H",
"version": "3.1"
},
"exploitabilityScore": 3.9,
"impactScore": 6.0,
"source": "security-advisories@github.com",
"type": "Secondary"
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2026-44327",
"options": [
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"exploitation": "poc"
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{
"automatable": "yes"
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{
"technicalImpact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-05-28T14:38:50.246985Z",
"version": "2.0.3"
}
}
]
},
"published": "2026-05-27T17:16:38.203",
"references": [
{
"source": "security-advisories@github.com",
"tags": [
"Exploit",
"Issue Tracking"
],
"url": "https://github.com/free5gc/free5gc/issues/861"
},
{
"source": "security-advisories@github.com",
"tags": [
"Exploit",
"Vendor Advisory"
],
"url": "https://github.com/free5gc/free5gc/security/advisories/GHSA-cmpj-2x3g-m7g3"
},
{
"source": "security-advisories@github.com",
"tags": [
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"Patch"
],
"url": "https://github.com/free5gc/nef/pull/23"
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}
],
"sourceIdentifier": "security-advisories@github.com",
"vulnStatus": "Analyzed",
"weaknesses": [
{
"description": [
{
"lang": "en",
"value": "CWE-306"
},
{
"lang": "en",
"value": "CWE-862"
}
],
"source": "security-advisories@github.com",
"type": "Secondary"
}
]
}
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Browse all ATT&CK techniques and the vulnerabilities related to each.
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