CVE-2026-39386
Neko is a a self-hosted virtual browser that runs in Docker and uses WebRTC In versions 3.0.0 through 3.0.10 and 3.1.0 through 3.1.1, any authenticated user can immediately obtain full administrative control of the entire Neko instance (member management, room settings, broadcast control, session termination, etc.). This results in a complete compromise of the instance. The vulnerability has been patched in v3.0.11 and v3.1.2.
Leer descripción completaMostrar menos
If upgrading is not immediately possible, the following mitigations can reduce risk: Restrict access to trusted users only (avoid granting accounts to untrusted parties); ensure all user passwords are strong and only shared with trusted individuals; run the instance only when needed; avoid leaving it continuously exposed; place the instance behind authentication layers such as a reverse proxy with additional access controls; disable or restrict access to the /api/profile endpoint if feasible; and/or monitor for suspicious privilege changes or unexpected administrative actions. Note that these are temporary mitigations and do not fully eliminate the vulnerability. Upgrading is strongly recommended.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- Puntuación base: 8.8
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.64%
- Percentil entre todas las CVEs puntuadas: 49
- Fecha de la puntuación: 5/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
🎯 Técnicas ATT&CK
Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.
- Explotación
T1210Exploitation of Remote Serviceslateral movement75 % - Impacto principal
T1068Exploitation for Privilege Escalationprivilege escalation85 % - Impacto secundario
T1078Valid Accountsstealth · persistence · privilege escalation · initial access80 %
Usuario autenticado (PR:L, red sin privilegios locales) accede a servicio remoto (Neko en Docker) para obtener control administrativo completo, escalando privilegios y comprometiendo cuentas.
Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.
🛡️ Mitigaciones ATT&CK que cubren estas técnicas
Tecnologías afectadas (1)
CWE
- CWE-20, CWE-269, CWE-284, CWE-639, CWE-862
Referencias
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-39386",
"cveTags": [],
"metrics": {
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2026-39386",
"role": "CISA Coordinator",
"options": [
{
"exploitation": "none"
},
{
"automatable": "no"
},
{
"technicalImpact": "total"
}
],
"version": "2.0.3",
"timestamp": "2026-04-21T00:00:00+00:00"
}
}
],
"cvssMetricV31": [
{
"type": "Secondary",
"source": "security-advisories@github.com",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 8.8,
"attackVector": "NETWORK",
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"integrityImpact": "HIGH",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "HIGH",
"privilegesRequired": "LOW",
"confidentialityImpact": "HIGH"
},
"impactScore": 5.9,
"exploitabilityScore": 2.8
}
]
},
"affected": [
{
"source": "security-advisories@github.com",
"affectedData": [
{
"vendor": "m1k1o",
"product": "neko",
"versions": [
{
"status": "affected",
"version": ">= 3.0.0, < 3.0.11"
},
{
"status": "affected",
"version": ">= 3.1.0, < 3.1.2"
}
]
}
]
}
],
"published": "2026-04-21T01:16:06.217",
"references": [
{
"url": "https://github.com/m1k1o/neko/releases/tag/v3.0.11",
"tags": [
"Product"
],
"source": "security-advisories@github.com"
},
{
"url": "https://github.com/m1k1o/neko/releases/tag/v3.1.2",
"tags": [
"Product"
],
"source": "security-advisories@github.com"
},
{
"url": "https://github.com/m1k1o/neko/security/advisories/GHSA-2gw9-c2r2-f5qf",
"tags": [
"Mitigation",
"Vendor Advisory"
],
"source": "security-advisories@github.com"
}
],
"vulnStatus": "Analyzed",
"weaknesses": [
{
"type": "Secondary",
"source": "security-advisories@github.com",
"description": [
{
"lang": "en",
"value": "CWE-20"
},
{
"lang": "en",
"value": "CWE-269"
},
{
"lang": "en",
"value": "CWE-284"
},
{
"lang": "en",
"value": "CWE-639"
},
{
"lang": "en",
"value": "CWE-862"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "Neko is a a self-hosted virtual browser that runs in Docker and uses WebRTC In versions 3.0.0 through 3.0.10 and 3.1.0 through 3.1.1, any authenticated user can immediately obtain full administrative control of the entire Neko instance (member management, room settings, broadcast control, session termination, etc.). This results in a complete compromise of the instance. The vulnerability has been patched in v3.0.11 and v3.1.2. If upgrading is not immediately possible, the following mitigations can reduce risk: Restrict access to trusted users only (avoid granting accounts to untrusted parties); ensure all user passwords are strong and only shared with trusted individuals; run the instance only when needed; avoid leaving it continuously exposed; place the instance behind authentication layers such as a reverse proxy with additional access controls; disable or restrict access to the /api/profile endpoint if feasible; and/or monitor for suspicious privilege changes or unexpected administrative actions. Note that these are temporary mitigations and do not fully eliminate the vulnerability. Upgrading is strongly recommended."
}
],
"lastModified": "2026-06-17T10:42:01.860",
"configurations": [
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:a:m1k1o:neko:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "58BE7A22-09E6-4816-92B2-068D5BA33669",
"versionEndExcluding": "3.0.11",
"versionStartIncluding": "3.0.0"
},
{
"criteria": "cpe:2.3:a:m1k1o:neko:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "9C19A8F7-3E62-4599-B3DF-FA374D5F4F8A",
"versionEndExcluding": "3.1.2",
"versionStartIncluding": "3.1.0"
}
],
"operator": "OR"
}
]
}
],
"sourceIdentifier": "security-advisories@github.com"
}