CVE-2026-85185
Path traversal in the btrfs storage driver in Canonical LXD versions 4.0.2 and later (fixed in…
- Risk score
- 63/100
- CVSS
- 9.6 v3.1
- Exploit chance (30 days)
- 0.4%
- Published
- 28 Sep 2026
Open in the live forecast Today's forecast
What to know
- What it is
- 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…
- Affected
- See advisory
- Fix
- Upgrade the product to 4.0.14, 5.0.10, 5.21.8 or 6.10 (whichever matches your release line), or later.
- Exploitation
- No known exploitation
Why it is Amber
- CVSS 9.6 critical
References
Original description
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.
Last activity 28 Sep 2026. Patch Forecast updates every hour.