CVE-2026-103474
yii2-starter-kit through 4.2.0 fails to validate file types in the backend storage upload actions, allowing authenticated managers to upload PHP files. Attackers with manager role can upload PHP scripts to the web-accessible storage directory and request them to execute arbitrary code on the server.
CVSS
- Versión: 4.0
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/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: 8.7
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.39%
- Percentil entre todas las CVEs puntuadas: 31
- 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
T1210Exploitation of Remote Serviceslateral movement75 % - Impacto principal
T1505.003Web Shellpersistence85 % - Impacto secundario
T1059.007JavaScriptexecution70 %
Autenticado con rol manager explota validación deficiente de tipos de archivo (CWE-434) en acciones de carga remota, sube PHP a directorio accesible web (web shell) y ejecuta código arbitrario en servidor.
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-434
Referencias
- https://github.com/yii-starter-kit/yii2-starter-kit
- https://github.com/yii-starter-kit/yii2-starter-kit/blob/cc2c451e8c959c7300b04efea597706a38609f58/backend/modules/file/controllers/StorageController.php#L36
- https://github.com/yii-starter-kit/yii2-starter-kit/issues/797
- https://www.vulncheck.com/advisories/yii2-starter-kit-through-4.2.0-unrestricted-file-upload-rce
JSON original (NVD)
Mostrar
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"affected": [
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"affectedData": [
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"value": "yii2-starter-kit through 4.2.0 fails to validate file types in the backend storage upload actions, allowing authenticated managers to upload PHP files. Attackers with manager role can upload PHP scripts to the web-accessible storage directory and request them to execute arbitrary code on the server."
}
],
"lastModified": "2026-09-30T19:08:43.927",
"sourceIdentifier": "disclosure@vulncheck.com"
}