CVE-2026-82531
Smarty before 4.5.8 and 5.x before 5.8.5 contains a code injection vulnerability where the top-level nocache_hash is never restored during extends:/multi-component template inheritance, leaving it null. Attackers can supply assigned data containing a forged SmartyNocache marker that is copied verbatim into the regenerated PHP cache file, executing arbitrary PHP on include for remote code execution.
CVSS
- Versión: 4.0
- Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
- Puntuación base: 9.2
Probabilidad de explotación (EPSS)
FIRST aún no ha puntuado esta CVE (habitual en CVEs muy recientes o rechazadas).
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 access92 % - Impacto principal
T1059Command and Scripting Interpreterexecution90 %
Vulnerabilidad en aplicación web remota (Smarty) sin requerir autenticación (PR:N, UI:N); inyección de código PHP que se ejecuta en la regeneración del cache. CWE-94 (code injection) confirma T1059.
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-94
Referencias
- https://github.com/smarty-php/smarty/commit/1cba51cb813563eb61d963c83d28cd59f26b858d
- https://github.com/smarty-php/smarty/commit/c0fdd4824aca4f67e814b50703cfee1dfde41414
- https://github.com/smarty-php/smarty/releases/tag/v4.5.8
- https://github.com/smarty-php/smarty/releases/tag/v5.8.5
- https://github.com/smarty-php/smarty/security/advisories/GHSA-3w63-v7pm-cq9x
- https://www.vulncheck.com/advisories/smarty-before-4.5.8-and-5-x-before-5.8.5-php-code-injection-via-extends-inheritance-cache
- https://github.com/smarty-php/smarty/security/advisories/GHSA-3w63-v7pm-cq9x
JSON original (NVD)
Mostrar
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