CVE-2026-85526Path traversal via Btrfs optimized-backup subvolumes[].path enables root file/dir manipulation in LXD

Descripción

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.

Datos: CVE.org, NVD, CISA KEV, FIRST EPSS, Ubuntu. Se publican tal como los indican las fuentes, en inglés.

Productos y versiones afectados

Referencias y parches

• https://github.com/canonical/lxd/security/advisories/GHSA-h85r-gjgx-g2rv vendor-advisoryissue-tracking
• https://github.com/canonical/lxd-private/pull/87 patch
• https://github.com/canonical/lxd-private/pull/105 patch
• https://github.com/canonical/lxd-private/pull/104 patch
• https://github.com/canonical/lxd-private/pull/103 patch
• https://github.com/canonical/lxd-private/pull/84 patch