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

No history.

Information

Published : 2026-04-09 10:16

Updated : 2026-06-17 10:38

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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