CVE-2026-91771
Weights & Biases wandb before 0.29.0 fails to validate the file name from server responses in the File.download function, allowing path traversal attacks. Attackers controlling the backend can supply file names with directory traversal sequences to write files outside the intended download directory, potentially enabling code execution through modification of shell startup files or Python import paths.
CVSS
- Versión: 4.0
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/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: 8.7
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 1.17%
- Percentil entre todas las CVEs puntuadas: 66
- 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.
- Explotación
T1203Exploitation for Client Executionexecution85 % - Impacto principal
T1005Data from Local Systemcollection80 % - Impacto secundario
T1059Command and Scripting Interpreterexecution75 %
UI:R (requiere interacción del usuario para descargar) → T1203 (ejecución en cliente). Path traversal en descarga puede leer archivos (T1005) o ejecutar código modificando startup files o imports (T1059).
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
Tecnologías afectadas (1)
⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.
CWE
- CWE-22
Referencias
- https://github.com/wandb/wandb
- https://github.com/wandb/wandb/blob/v0.27.2/wandb/apis/public/files.py#L319-L347
- https://github.com/wandb/wandb/commit/e52558f3a6a94ea816af74969a13a35e5904cad6
- https://github.com/wandb/wandb/issues/12592
- https://github.com/wandb/wandb/releases/tag/v0.29.0
- https://www.vulncheck.com/advisories/weights-biases-wandb-before-0.29.0-path-traversal-via-file-download
JSON original (NVD)
Mostrar
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"value": "Weights & Biases wandb before 0.29.0 fails to validate the file name from server responses in the File.download function, allowing path traversal attacks. Attackers controlling the backend can supply file names with directory traversal sequences to write files outside the intended download directory, potentially enabling code execution through modification of shell startup files or Python import paths."
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"sourceIdentifier": "disclosure@vulncheck.com"
}