CVE-2026-12411 | Broken Access Control in the devLXDInstancePatchHandler comp… | CVSS 8.4 HIGH

Description

Broken Access Control in the devLXDInstancePatchHandler component of Canonical LXD allows an untrusted guest to mount, read, and overwrite another guest's custom storage volume via a crafted device PATCH request over /dev/lxd when security.devlxd.management.volumes is enabled.

Metadata

CVE ID: CVE-2026-12411
State: PUBLISHED
Assigner: canonical
Reserved: 2026-06-16 15:07 UTC
Published: 2026-06-26 15:27 UTC
Last updated: 2026-06-26 16:02 UTC
Primary CWE: CWE-639
CWE-639 Authorization bypass through User-Controlled key
Vendor / Product: Canonical / lxd
Sources: cve.org · NVD

Severity & Metrics

8.4 HIGH CVSS 3.1

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N

SSVC — CISA Coordinator

Exploitation: PoC
Automatable: no
Tech. Impact: total

Affected products (1)

Vendor	Product	Platform	Versions
Canonical	lxd	Linux	6.6 < 6.9

Weakness (CWE)

CWE	Source	Description
CWE-639	cna	CWE-639 Authorization bypass through User-Controlled key
CWE-862	cna	CWE-862 Missing Authorization

CVSS scores (1)

Score	Severity	Version	Source	Vector
8.4	HIGH	3.1	cna	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N

References (2)

Cross-guest volume hijack via DevLXD device patch https://github.com/canonical/lxd/security/advisories/GHSA-hhf9-qw4v-72xp
Security fixes from the 6.9 release https://github.com/canonical/lxd/pull/18585