CVE-2026-40518

ByteDance DeerFlow before commit 2176b2b contains a path traversal and arbitrary file write vulnerability in bootstrap-mode custom-agent creation where the agent name validation is bypassed. Attackers can supply traversal-style values or absolute paths as the agent name to influence directory creation and write files outside the intended custom-agent directory, potentially achieving arbitrary file write on the system subject to filesystem permissions.

CVSS v3 7.1 HIGH

7.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 4.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/bytedance/deer-flow/commit/2176b2bbfccfce25ceee08318813f96d843a13fd	Patch
https://github.com/bytedance/deer-flow/pull/2274	Issue Tracking Patch
https://www.vulncheck.com/advisories/bytedance-deerflow-path-traversal-and-arbitrary-file-write-via-bootstrap-mode	Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:bytedance:deerflow:2.0-m0:*:*:*:*:*:*:*

History

26 Oct 2026, 21:10

Type	Values Removed	Values Added
Summary		(es) ByteDance DeerFlow antes del commit 2176b2b contiene una vulnerabilidad de salto de ruta y escritura arbitraria de archivos en la creación de agentes personalizados en modo bootstrap, donde se omite la validación del nombre del agente. Los atacantes pueden proporcionar valores de estilo de salto de ruta o rutas absolutas como nombre del agente para influir en la creación de directorios y escribir archivos fuera del directorio de agentes personalizados previsto, logrando potencialmente la escritura arbitraria de archivos en el sistema sujeta a los permisos del sistema de archivos.

Information

Published : 2026-04-17 17:17

Updated : 2026-10-26 21:10

NVD link : CVE-2026-40518

Mitre link : CVE-2026-40518

CVE.ORG link : CVE-2026-40518

JSON object : View

Products Affected

bytedance

deerflow

CWE

CWE-22

Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

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