CVE-2021-29440
Grav is a file based Web-platform. Twig processing of static pages can be enabled in the front matter by any administrative user allowed to create or edit pages. As the Twig processor runs unsandboxed, this behavior can be used to gain arbitrary code execution and elevate privileges on the instance. The issue was addressed in version 1.7.11.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
- Puntuación base: 7.2
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 31%
- Percentil entre todas las CVEs puntuadas: 98
- Fecha de la puntuación: 7/10/2026
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).
💥 Exploits públicos
Hay código de explotación o plantillas de detección públicos. No es lo mismo que explotación activa confirmada (KEV), pero aumenta el riesgo: parchee con prioridad.
- Publicado en Exploit-DB · Grav CMS 1.7.10 - Server-Side Template Injection (SSTI) (Authenticated) (7/6/2021)
- Prueba de concepto en GitHub (no verificada) · Lista de pruebas de concepto en GitHub
⚠️ Las pruebas de concepto de GitHub no están verificadas: algunas son falsas o contienen malware. No las ejecute nunca fuera de un laboratorio aislado.
Tecnologías afectadas (1)
CWE
- CWE-94
Referencias
- http://packetstormsecurity.com/files/162987/Grav-CMS-1.7.10-Server-Side-Template-Injection.html
- https://blog.sonarsource.com/grav-cms-code-execution-vulnerabilities
- https://github.com/getgrav/grav/security/advisories/GHSA-g8r4-p96j-xfxc
- https://packagist.org/packages/getgrav/grav
- http://packetstormsecurity.com/files/162987/Grav-CMS-1.7.10-Server-Side-Template-Injection.html
- https://blog.sonarsource.com/grav-cms-code-execution-vulnerabilities
- https://github.com/getgrav/grav/security/advisories/GHSA-g8r4-p96j-xfxc
- https://packagist.org/packages/getgrav/grav
JSON original (NVD)
Mostrar
{
"id": "CVE-2021-29440",
"cveTags": [],
"metrics": {
"cvssMetricV2": [
{
"type": "Primary",
"source": "nvd@nist.gov",
"cvssData": {
"version": "2.0",
"baseScore": 6.5,
"accessVector": "NETWORK",
"vectorString": "AV:N/AC:L/Au:S/C:P/I:P/A:P",
"authentication": "SINGLE",
"integrityImpact": "PARTIAL",
"accessComplexity": "LOW",
"availabilityImpact": "PARTIAL",
"confidentialityImpact": "PARTIAL"
},
"acInsufInfo": false,
"impactScore": 6.4,
"baseSeverity": "MEDIUM",
"obtainAllPrivilege": false,
"exploitabilityScore": 8,
"obtainUserPrivilege": false,
"obtainOtherPrivilege": false,
"userInteractionRequired": false
}
],
"cvssMetricV31": [
{
"type": "Secondary",
"source": "security-advisories@github.com",
"cvssData": {
"scope": "CHANGED",
"version": "3.1",
"baseScore": 8.4,
"attackVector": "NETWORK",
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:H/I:H/A:H",
"integrityImpact": "HIGH",
"userInteraction": "REQUIRED",
"attackComplexity": "LOW",
"availabilityImpact": "HIGH",
"privilegesRequired": "HIGH",
"confidentialityImpact": "HIGH"
},
"impactScore": 6,
"exploitabilityScore": 1.7
},
{
"type": "Primary",
"source": "nvd@nist.gov",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 7.2,
"attackVector": "NETWORK",
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H",
"integrityImpact": "HIGH",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "HIGH",
"privilegesRequired": "HIGH",
"confidentialityImpact": "HIGH"
},
"impactScore": 5.9,
"exploitabilityScore": 1.2
}
]
},
"affected": [
{
"source": "security-advisories@github.com",
"affectedData": [
{
"vendor": "getgrav",
"product": "grav",
"versions": [
{
"status": "affected",
"version": "< 1.7.11"
}
]
}
]
}
],
"published": "2021-04-13T20:15:22.360",
"references": [
{
"url": "http://packetstormsecurity.com/files/162987/Grav-CMS-1.7.10-Server-Side-Template-Injection.html",
"tags": [
"Exploit",
"Third Party Advisory",
"VDB Entry"
],
"source": "security-advisories@github.com"
},
{
"url": "https://blog.sonarsource.com/grav-cms-code-execution-vulnerabilities",
"tags": [
"Exploit",
"Third Party Advisory"
],
"source": "security-advisories@github.com"
},
{
"url": "https://github.com/getgrav/grav/security/advisories/GHSA-g8r4-p96j-xfxc",
"tags": [
"Third Party Advisory"
],
"source": "security-advisories@github.com"
},
{
"url": "https://packagist.org/packages/getgrav/grav",
"tags": [
"Product",
"Third Party Advisory"
],
"source": "security-advisories@github.com"
},
{
"url": "http://packetstormsecurity.com/files/162987/Grav-CMS-1.7.10-Server-Side-Template-Injection.html",
"tags": [
"Exploit",
"Third Party Advisory",
"VDB Entry"
],
"source": "af854a3a-2127-422b-91ae-364da2661108"
},
{
"url": "https://blog.sonarsource.com/grav-cms-code-execution-vulnerabilities",
"tags": [
"Exploit",
"Third Party Advisory"
],
"source": "af854a3a-2127-422b-91ae-364da2661108"
},
{
"url": "https://github.com/getgrav/grav/security/advisories/GHSA-g8r4-p96j-xfxc",
"tags": [
"Third Party Advisory"
],
"source": "af854a3a-2127-422b-91ae-364da2661108"
},
{
"url": "https://packagist.org/packages/getgrav/grav",
"tags": [
"Product",
"Third Party Advisory"
],
"source": "af854a3a-2127-422b-91ae-364da2661108"
}
],
"vulnStatus": "Modified",
"weaknesses": [
{
"type": "Secondary",
"source": "security-advisories@github.com",
"description": [
{
"lang": "en",
"value": "CWE-94"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "Grav is a file based Web-platform. Twig processing of static pages can be enabled in the front matter by any administrative user allowed to create or edit pages. As the Twig processor runs unsandboxed, this behavior can be used to gain arbitrary code execution and elevate privileges on the instance. The issue was addressed in version 1.7.11."
},
{
"lang": "es",
"value": "Grav es una plataforma web basada en archivos. El procesamiento de Twig de páginas estáticas puede ser habilitado en la materia inicial por cualquier usuario administrativo autorizado para crear o editar páginas. Como el procesador Twig se ejecuta sin sandbox, este comportamiento puede ser usado para obtener una ejecución de código arbitraria y elevar los privilegios en la instancia. El problema se solucionó en la versión 1.7.11"
}
],
"lastModified": "2026-06-17T03:47:38.757",
"configurations": [
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:a:getgrav:grav:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "3DDB0D78-D53F-4A5F-B1EB-0A4E3E986E30",
"versionEndExcluding": "1.7.11"
}
],
"operator": "OR"
}
]
}
],
"sourceIdentifier": "security-advisories@github.com"
}