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CVE-2026-33946

Estado: AnalizadaAlta (8.2)—

MCP Ruby SDK is the official Ruby SDK for Model Context Protocol servers and clients. Prior to version 0.9.2, the Ruby SDK's streamable_http_transport.rb implementation contains a session hijacking vulnerability. An attacker who obtains a valid session ID can completely hijack the victim's Server-Sent Events (SSE) stream and intercept all real-time data. Version 0.9.2 contains a patch.

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.

Vulnerabilidad de secuestro de sesión en SDK Ruby expuesto en red (AV:N, PR:N). Impacto: interceptación de datos en tiempo real (T1041) y man-in-the-middle en sesiones SSE (T1557).

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

Network SegmentationNetwork Intrusion PreventionLimit Access to Resource Over NetworkFilter Network TrafficVulnerability ScanningUser Training

Tecnologías afectadas (1)

Lfprojects — MCP Ruby SDK

CWE

Referencias

JSON original (NVD)

Mostrar
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