CVE-2026-49991

Estado: AplazadaAlta (8.6)—

RustFS is a distributed object storage system built in Rust. In 1.0.0-beta.4, authenticated users with only PutObject permission on their own bucket can exploit a path traversal vulnerability in the Snowball auto-extract feature to write arbitrary objects into other users' buckets, completely breaking multi-tenant isolation. The vulnerability chains three flaws: No ../ sanitization in tar entry key normalization; IAM wildcard matching uses raw (uncleaned) paths; and Filesystem path cleaning resolves ../ across bucket boundaries.

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N
Puntuación base: 8.6

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.41%
Percentil entre todas las CVEs puntuadas: 34
Fecha de la puntuación: 5/10/2026

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 principalT1565.002 Transmitted Data Manipulationimpact90 %
Impacto secundarioT1078.001 Default Accountsstealth · persistence · privilege escalation · initial access75 %

Acceso remoto de red sin privilegios (AV:N/PR:N) explotando vulnerabilidad en aplicación (path traversal en RustFS). Impacto: modificación de datos en buckets ajenos (T1565.002) y acceso no autorizado a datos de otros usuarios (T1078.001 por bypass de aislamiento multitenancy).

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

Vulnerability Scanning Privileged Account Management Password Policies Network Segmentation Multi-factor Authentication Limit Access to Resource Over Network

Tecnologías afectadas (1)

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

Rustfs — Rustfs^AI

CWE

CWE-22, CWE-862

Referencias

JSON original (NVD)

Mostrar

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