CVE-2021-21311
Adminer is an open-source database management in a single PHP file. In adminer from version 4.0.0 and before 4.7.9 there is a server-side request forgery vulnerability. Users of Adminer versions bundling all drivers (e.g. `adminer.php`) are affected. This is fixed in version 4.7.9.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N
- Puntuación base: 7.2
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 98%
- Percentil entre todas las CVEs puntuadas: 100
- 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).
CISA KEV — explotada activamente
- Añadida al catálogo: 29/9/2025
- Plazo de remediación: 20/10/2025
- Uso conocido en ransomware: Unknown
🎯 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 access90 % - Impacto principal
T1090Proxycommand and control85 % - Impacto secundario
T1005Data from Local Systemcollection70 %
SSRF en Adminer (CWE-918) accesible remotamente sin autenticación (AV:N/PR:N/UI:N). Permite proxy/SSRF (T1090) y acceso a datos locales (T1005) vía consultas a BD internas.
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 (2)
CWE
- CWE-918
Referencias
- https://github.com/vrana/adminer/commit/ccd2374b0b12bd547417bf0dacdf153826c83351
- https://github.com/vrana/adminer/files/5957311/Adminer.SSRF.pdf
- https://github.com/vrana/adminer/security/advisories/GHSA-x5r2-hj5c-8jx6
- https://lists.debian.org/debian-lts-announce/2021/03/msg00002.html
- https://packagist.org/packages/vrana/adminer
- https://github.com/vrana/adminer/commit/ccd2374b0b12bd547417bf0dacdf153826c83351
- https://github.com/vrana/adminer/files/5957311/Adminer.SSRF.pdf
- https://github.com/vrana/adminer/security/advisories/GHSA-x5r2-hj5c-8jx6
- https://lists.debian.org/debian-lts-announce/2021/03/msg00002.html
- https://packagist.org/packages/vrana/adminer
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-21311
JSON original (NVD)
Mostrar
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