CVE-2026-34178

In Canonical LXD before 6.8, the backup import path validates project restrictions against backup/index.yaml in the supplied tar archive but creates the instance from backup/container/backup.yaml, a separate file in the same archive that is never checked against project restrictions. An authenticated remote attacker with instance-creation permission in a restricted project can craft a backup archive where backup.yaml carries restricted settings such as security.privileged=true or raw.lxc directives, bypassing all project restriction enforcement and allowing full host compromise.

CVSS v3 9.1 CRITICAL

9.1^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 2.3 / Impact : 6.0

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required HIGH

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope CHANGED

References

Link	Resource
https://github.com/canonical/lxd/pull/17921	Issue Tracking
https://github.com/canonical/lxd/security/advisories/GHSA-q96j-3fmm-7fv4	Exploit Third Party Advisory
https://github.com/canonical/lxd/security/advisories/GHSA-q96j-3fmm-7fv4	Exploit Third Party Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:canonical:lxd::::::::
	cpe:2.3:a:canonical:lxd::::::::
	cpe:2.3:a:canonical:lxd::::::::

History

26 Oct 2026, 21:10

Type	Values Removed	Values Added
Summary		(es) En Canonical LXD anterior a 6.8, la ruta de importación de la copia de seguridad valida las restricciones del proyecto contra backup/index.yaml en el archivo tar suministrado pero crea la instancia a partir de backup/container/backup.yaml, un archivo separado en el mismo archivo que nunca se verifica contra las restricciones del proyecto. Un atacante remoto autenticado con permiso de creación de instancias en un proyecto restringido puede elaborar un archivo de copia de seguridad donde backup.yaml contenga configuraciones restringidas como security.privileged=true o directivas raw.lxc, eludiendo toda la aplicación de restricciones del proyecto y permitiendo el compromiso total del host.

Information

Published : 2026-04-09 10:16

Updated : 2026-10-26 21:10

NVD link : CVE-2026-34178

Mitre link : CVE-2026-34178

CVE.ORG link : CVE-2026-34178

JSON object : View

Products Affected

canonical

lxd

CWE

CWE-20

Improper Input Validation

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