CVE-2026-85185 (GCVE-0-2026-85185)

Vulnerability from cvelistv5 – Published: 2026-09-28 13:21 – Updated: 2026-09-28 16:32
VLAI
Title
Path traversal in LXD btrfs storage driver allows arbitrary file deletion and write on host as root
Summary
Path traversal in the btrfs storage driver in Canonical LXD versions 4.0.2 and later (fixed in 4.0.14, 5.0.10, 5.21.8 and 6.10) on Linux allows an authenticated client with permission to create instances in a project to delete arbitrary files on the host as root. On hosts whose root filesystem is btrfs, the client can also place attacker-controlled content at arbitrary host paths, leading to full host compromise. The client does this with a crafted subvolume path containing ../ sequences, sent in either of two ways: in the optimized_header.yaml of an optimized btrfs backup, or in the btrfs migration header sent by a malicious migration source.
Severity
9.6 (Critical)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:H
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-28 13:55 UTC
CWE
  • CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
Assigner
canonical CNA under the mitre root
CNA scorecard B 82/100 over 62 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Canonical LXD Affected: 4.0.2 , < 4.0.14 (semver)
Affected: 5.0.0 , < 5.0.10 (semver)
Affected: 5.21.0 , < 5.21.8 (semver)
Affected: 6.0 , < 6.10 (semver)
guessed Create a notification for this product.
Date Public
2026-09-25 03:00
Show details on NVD website
To clipboard 

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Solutions

CNA · canonical
Upgrade to LXD versions 4.0.14, 5.0.10, 5.21.8, 6.10 or later.

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