CVE-2026-34177

Canonical LXD versions 4.12 through 6.7 contain an incomplete denylist in isVMLowLevelOptionForbidden (lxd/project/limits/permissions.go), which omits raw.apparmor and raw.qemu.conf from the set of keys blocked under the restricted.virtual-machines.lowlevel=block project restriction. A remote attacker with can_edit permission on a VM instance in a restricted project can inject an AppArmor rule and a QEMU chardev configuration that bridges the LXD Unix socket into the guest VM, enabling privilege escalation to LXD cluster administrator and subsequently to host root.

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/17909	Issue Tracking
https://github.com/canonical/lxd/security/advisories/GHSA-fm2x-c5qw-4h6f	Third Party Advisory
https://github.com/canonical/lxd/security/advisories/GHSA-fm2x-c5qw-4h6f	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) Versiones de Canonical LXD 4.12 a 6.7 contienen una denylist incompleta en isVMLowLevelOptionForbidden (lxd/project/limits/permissions.go), que omite raw.apparmor y raw.qemu.conf del conjunto de claves bloqueadas bajo la restricción de proyecto restricted.virtual-machines.lowlevel=block. Un atacante remoto con permiso can_edit en una instancia de VM en un proyecto restringido puede inyectar una regla de AppArmor y una configuración de chardev de QEMU que conecta el socket Unix de LXD a la VM invitada, lo que permite la escalada de privilegios a administrador de clúster de LXD y, posteriormente, a root del host.

Information

Published : 2026-04-09 10:16

Updated : 2026-10-26 21:10

NVD link : CVE-2026-34177

Mitre link : CVE-2026-34177

CVE.ORG link : CVE-2026-34177

JSON object : View

Products Affected

canonical

lxd

CWE

CWE-184

Incomplete List of Disallowed Inputs

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