CVE-2026-66898: canonical lxd Path Traversal
Vulnerability summary
CVE-2026-66898 is a critical (CVSS 9.9) Path Traversal vulnerability in canonical lxd. EPSS estimates a 0.59% chance of exploitation in the next 30 days, higher than 47.1% of scored vulnerabilities. 1 public exploit is recorded.
Advisory lineage
Upstream 0 · Downstream 1 · Related 1Timeline
- 12-08-2026PublishedVulnerability first disclosed.
- 13-08-2026Last modifiedVulnerability information updated.
Description
A path traversal vulnerability in LXD allows an attacker to manipulate file system paths during backup import and restore operations. When importing or restoring a backup archive, LXD fails to validate instance and storage volume names contained within the archive metadata. An attacker can exploit this flaw by supplying a crafted backup archive with malicious instance or volume names containing path traversal sequences, potentially allowing file access or overwriting outside the designated restore directory.
CVSS metrics
4 scores · 4 sources · 1 version- OSV · UbuntuEcosystem advisory · calculated9.9CriticalCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
- OSV · DebianEcosystem advisory · calculated9.9CriticalCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
- NVDNIST9.9CriticalCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
EPSS trend
Probability
0.59%
Chance of exploitation in the next 30 days
Percentile
47%
Versus all other CVEs
30-day change
+0.16 pp
From 0.43% on 18-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
1 foundLxd
Maturity: poc
Weaknesses
CWE · root causeAffected systems
Canonical1 product
- lxd≥ 5.21.0, < 5.21.2 | ≥ 6.0, < 6.1 | ≥ 4.0.0, < 4.0.12 | ≥ 5.0.0, < 5.0.4 | ≥ 5.1, < 5.21.2 | 6.0
Debian1 product
- lxdAll versions (No fix recorded)
Ubuntu1 product
- lxdAll versions (No fix recorded)
3 vendors · 3 products
References
4 links- github.com/canonical/lxd/security/advisories/GHSA-m857-c7gc-c984VDB EntryVendor AdvisoryREPORTExploitMitigation