CVE-2026-104120

Estado: AplazadaMedia (5.5)—

A security vulnerability has been detected in modelcontextprotocol mcp-server-fetch and mcp-server-everything up to 2026.6.4. Affected is the function fetch_url of the file mcp_server_fetch/server.py of the component Fetch Tool. The manipulation of the argument url/path leads to server-side request forgery. The attack may be initiated remotely. The exploit has been disclosed publicly and may be used. The pull request to fix this issue awaits acceptance.

CVSS

Versión: 4.0
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P/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: 5.5

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.29%
Percentil entre todas las CVEs puntuadas: 20
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.

ExplotaciónT1190 Exploit Public-Facing Applicationinitial access85 %
Impacto principalT1090 Proxycommand and control80 %
Impacto secundarioT1005 Data from Local Systemcollection70 %

CWE-918 (SSRF) en componente Fetch Tool expuesto remotamente (AV:N/PR:N/UI:N) sin autenticación. El atacante manipula 'url/path' para desviar solicitudes del servidor a recursos internos, logrando proxy no autorizado y potencial acceso a datos internos.

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

Filter Network Traffic Vulnerability Scanning SSL/TLS Inspection Privileged Account Management Network Segmentation Network Intrusion Prevention

Tecnologías afectadas (2)

⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.

Modelcontextprotocol — MCP Server Everything^AI Modelcontextprotocol — MCP Server Fetch^AI

CWE

CWE-918

Referencias

JSON original (NVD)

Mostrar

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  "references": [
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      "url": "https://github.com/modelcontextprotocol/servers/issues/4492",
      "source": "cna@vuldb.com"
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      "url": "https://github.com/modelcontextprotocol/servers/pull/4890",
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