CVE-2026-63343

Incus is a system container and virtual machine manager. Prior to version 7.3.0, a malicious image containing a `metadata.yaml` symlink pointing to an arbitrary host path allows an authenticated Incus user to read or overwrite any file on the host as root via the instance metadata API. The `exec-output` and `templates/` paths were patched in a prior release using `Lstat` rejection and `os.OpenRoot` confinement; `metadata.yaml` was not included in either patch and remains exploitable. Version 7.3.0 patches the issue.

CVSS v3 9.9 CRITICAL

9.9^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.1 / Impact : 6.0

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope CHANGED

References

Link	Resource
https://github.com/lxc/incus/security/advisories/GHSA-fmjx-5j3g-997p

Configurations

No configuration.

History

15 Oct 2026, 19:10

Type	Values Removed	Values Added
Summary		(es) Incus es un gestor de contenedores de sistema y máquinas virtuales. Antes de la versión 7.3.0, una imagen maliciosa que contiene un enlace simbólico 'metadata.yaml' que apunta a una ruta de host arbitraria permite a un usuario autenticado de Incus leer o sobrescribir cualquier archivo en el host como root a través de la API de metadatos de la instancia. Las rutas 'exec-output' y 'templates/' fueron parcheadas en una versión anterior utilizando el rechazo de 'Lstat' y el confinamiento de 'os.OpenRoot'; 'metadata.yaml' no se incluyó en ninguno de los parches y sigue siendo explotable. La versión 7.3.0 parchea el problema.

Information

Published : 2026-08-21 15:16

Updated : 2026-10-15 19:10

NVD link : CVE-2026-63343

Mitre link : CVE-2026-63343

CVE.ORG link : CVE-2026-63343

JSON object : View

Products Affected

No product.

CWE

CWE-73

External Control of File Name or Path

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