CVE-2026-16033

CVE-2026-16033 is a path traversal vulnerability (CWE-22) in Canonical's LXD, scored 8.5 High (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:N). When processing image metadata templates for virtual machines (the QEMU driver), LXD fails to sanitize or restrict template file paths, so a crafted image archive containing traversal sequences can escape the instance templates directory on the host. An attacker who can supply or import such an image gains the ability to read arbitrary files on the host or create files anywhere the LXD daemon can write, potentially enabling credential theft and further host compromise. Any environment running affected LXD builds that launches virtual machines from image archives is exposed, particularly multi-tenant, cloud, or CI setups where users can import their own images. Exploitation is not known in the wild: the issue is not in CISA KEV, EPSS is 0.3% (22nd percentile), and the only public reference is Canonical's security advisory with a PoC (GHSA-9hcm-hxh5-7xxh).

What to do: Upgrade LXD to the fixed release identified in Canonical's security advisory GHSA-9hcm-hxh5-7xxh (exact fixed version numbers were not included in this dataset). Until patched, restrict who can import or launch VM images on LXD hosts and only use image archives from trusted sources. If untrusted images were processed on a host, audit for files created or modified outside the intended templates directory and review for signs of tampering.