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CVE-2026-55420

Estado: AnalizadaAlta (8.1)—

Discourse is an open-source discussion platform. Prior to 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5, under certain non-default configurations, processing of PDF uploads could be exploited to obtain RCE on the server. This issue is patched in 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5.

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).

🎯 Técnicas ATT&CK

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

AV:N sin autenticación y CWE-78 (OS Command Injection) permiten RCE remoto a través de procesamiento de PDFs; impacto de ejecución de comandos en el 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

Privileged Account ManagementVulnerability ScanningRestrict Web-Based ContentNetwork SegmentationLimit Software InstallationLimit Access to Resource Over Network

Tecnologías afectadas (1)

Discourse — Discourse

CWE

Referencias

JSON original (NVD)

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  "cveTags": [],
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          "role": "CISA Coordinator",
          "options": [
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              "exploitation": "none"
            },
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              "automatable": "no"
            },
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              "technicalImpact": "total"
            }
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          "version": "2.0.3",
          "timestamp": "2026-07-14T01:08:36.928611Z"
        }
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      "description": [
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    }
  ],
  "lastModified": "2026-07-14T02:16:56.050",
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