CVE-2026-63343Container-to-Host escape and Root access in Incus
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.
View on NVDAnalysis
Incus (el sucesor de LXD) presenta una vulnerabilidad crítica que permite a un usuario escapar de un contenedor o VM y obtener privilegios de root en el host. El fallo se activa mediante el uso de enlaces simbólicos maliciosos en el archivo metadata.yaml de una imagen, permitiendo leer o sobreescribir cualquier archivo del servidor físico.
Relevant roles
Severity
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:HCWE-73EPSS
No EPSS score yet (CVE may be too fresh).
Technical description
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.