CVE-2026-85526

Critical

Description

Path traversal in the Btrfs storage driver (unpackVolume) in Canonical LXD on Linux allows an authenticated user with instance creation privileges to delete or replace arbitrary files and directories on the host filesystem as root via a crafted subvolumes[].path entry in backup/optimized_header.yaml during a btrfs optimized backup import.

SeverityCritical

CVSS9.9

Exploit probability—

ProductLXD

PublishedSep 28, 2026

First seenSep 28, 2026

Weakness typeCWE-22Path traversal

How to fix

Update

Canonical LXD4.0.14, 5.0.10, 5.21.8, 6.10 or later

Patches

Vendor advisories

github.com/canonical/lxd/security/advisories/GHSA-h85r-gjgx-g2rv

Affected products

Product	Affected versions	Fixed in
Canonical LXD	4.0.0 ≤ v < 4.0.14, 5.0.0 ≤ v < 5.0.10, 5.21.0 ≤ v < 5.21.8, 6.0 ≤ v < 6.10	4.0.14, 5.0.10, 5.21.8, 6.10

Check your version

Choose the product and enter the version you run to see whether it falls in the affected range.

In the Intelligence 360 plan

Attack Surface Management

See the assets tied to your domains, the technologies they run and known vulnerabilities in one list.