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CVE-2026-33645

Estado: AnalizadaAlta (8.1)—

Fireshare facilitates self-hosted media and link sharing. In version 1.5.1, an authenticated path traversal vulnerability in Fireshare’s chunked upload endpoint allows an attacker to write arbitrary files outside the intended upload directory. The `checkSum` multipart field is used directly in filesystem path construction without sanitization or containment checks. This enables unauthorized file writes to attacker-chosen paths writable by the Fireshare process (e.g., container `/tmp`), violating integrity and potentially enabling follow-on attacks depending on deployment. Version 1.5.2 fixes the issue.

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.

Acceso red con PR:L y ausencia de UI:R → T1210. Path traversal (CWE-22) permite escritura arbitraria de archivos fuera del directorio destino (T1565). Archivos en `/tmp` pueden ser aprovechados para manipulación de librerías (T1574).

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 File and Directory PermissionsNetwork SegmentationUpdate SoftwareApplication Developer GuidanceVulnerability ScanningUser Account Management

Tecnologías afectadas (1)

Shaneisrael — Fireshare

CWE

Referencias

JSON original (NVD)

Mostrar
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