CVE-2026-52539
Outstatic CMS <= 2.1.9 contains a hardcoded JWT signing secret. When the OST_TOKEN_SECRET environment variable is not set, the application falls back to the default value which is publicly visible in the source code repository. An unauthenticated remote attacker can exploit this by forging JWT session tokens with arbitrary user data and full administrative permissions.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
- Puntuación base: 9.1
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.53%
- Percentil entre todas las CVEs puntuadas: 43
- Fecha de la puntuación: 6/10/2026
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
T1190Exploit Public-Facing Applicationinitial access85 % - Impacto principal
T1078.001Default Accountsstealth · persistence · privilege escalation · initial access90 %
AV:N/AC:L/PR:N permite explotación remota sin autenticación (T1190). El secreto JWT hardcodeado permite falsificar tokens con permisos administrativos, otorgando acceso con credenciales válidas (T1078.001).
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)
⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.
CWE
- CWE-798
Referencias
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-52539",
"cveTags": [],
"metrics": {
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2026-52539",
"role": "CISA Coordinator",
"options": [
{
"exploitation": "none"
},
{
"automatable": "yes"
},
{
"technicalImpact": "total"
}
],
"version": "2.0.3",
"timestamp": "2026-07-31T11:43:18.166882Z"
}
}
],
"cvssMetricV31": [
{
"type": "Secondary",
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 9.1,
"attackVector": "NETWORK",
"baseSeverity": "CRITICAL",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N",
"integrityImpact": "HIGH",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "NONE",
"privilegesRequired": "NONE",
"confidentialityImpact": "HIGH"
},
"impactScore": 5.2,
"exploitabilityScore": 3.9
}
]
},
"affected": [
{
"source": "cve@mitre.org",
"affectedData": [
{
"vendor": "n/a",
"product": "n/a",
"versions": [
{
"status": "affected",
"version": "n/a"
}
]
}
]
}
],
"published": "2026-07-30T21:17:47.213",
"references": [
{
"url": "https://github.com/avitorio/outstatic",
"source": "cve@mitre.org"
},
{
"url": "https://github.com/avitorio/outstatic/blob/canary/packages/outstatic/src/utils/constants.ts",
"source": "cve@mitre.org"
}
],
"vulnStatus": "Deferred",
"weaknesses": [
{
"type": "Secondary",
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"description": [
{
"lang": "en",
"value": "CWE-798"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "Outstatic CMS <= 2.1.9 contains a hardcoded JWT signing secret. When the OST_TOKEN_SECRET environment variable is not set, the application falls back to the default value which is publicly visible in the source code repository. An unauthenticated remote attacker can exploit this by forging JWT session tokens with arbitrary user data and full administrative permissions."
}
],
"lastModified": "2026-07-31T12:16:50.780",
"sourceIdentifier": "cve@mitre.org"
}