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CVE-2021-26829

Estado: AnalizadaMedia (5.4)⚠ Explotación activa

OpenPLC ScadaBR through 0.9.1 on Linux and through 1.12.4 on Windows allows stored XSS via system_settings.shtm.

CVSS

Probabilidad de explotación (EPSS)

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

🎯 Técnicas ATT&CK

Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.

XSS almacenado en system_settings.shtm permite inyectar código JavaScript ejecutable en navegador del usuario autenticado. Requiere interacción del usuario (UI:R) para activarse, típico de T1189.

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

Restrict Web-Based ContentUser TrainingExecution PreventionBehavior Prevention on EndpointDisable or Remove Feature or ProgramApplication Isolation and Sandboxing

Tecnologías afectadas (1)

Scadabr — Scadabr

CWE

Referencias

JSON original (NVD)

Mostrar
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    },
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      "value": "OpenPLC ScadaBR versiones hasta 0.9.1 en Linux y versiones hasta 1.12.4 en Windows, permite un ataque de tipo XSS almacenado por medio del archivo system_settings.shtm"
    }
  ],
  "lastModified": "2026-06-17T03:43:50.063",
  "cisaActionDue": "2025-12-19",
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  "cisaVulnerabilityName": "OpenPLC ScadaBR Cross-site Scripting Vulnerability"
}