Path traversal in LXD btrfs storage driver allows arbitrary file deletion and write on host as root
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.
CVE-2026-85185
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-85185
LXD
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://github.com/canonical/lxd",
"vendor": "Canonical",
"product": "LXD",
"versions": [
{
"status": "affected",
"version": "4.0.2",
"lessThan": "4.0.14",
"versionType": "semver"
},
{
"status": "affected",
"version": "5.0.0",
"lessThan": "5.0.10",
"versionType": "semver"
},
{
"status": "affected",
"version": "5.21.0",
"lessThan": "5.21.8",
"versionType": "semver"
},
{
"status": "affected",
"version": "6.0",
"lessThan": "6.10",
"versionType": "semver"
}
],
"platforms": [
"Linux"
],
"packageName": "LXD",
"defaultStatus": "unaffected"
}
]- Related CVEs
- CVE-2026-85185
Source reference:
/cveMetadata/cveId
Publisher severity
critical
Source reference: /containers/cna/metrics
- Event
- #3208 · Revision 1
- Added to Heist Feed
- Publisher date