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TI-2026-47474 Aliases CVE-2026-66897

Instance template path traversal allows arbitrary host file write as root

Priority MEDIUM 44CWE-22Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA.

Summary

A path traversal vulnerability in LXD's instance template processing allows an attacker with container edit permissions, or any user launching a crafted image, to overwrite arbitrary files on the host system as root. When processing target template paths specified in metadata.yaml, LXD validates the path against a confined os.Root directory handle but subsequently opens and creates the file using os.Create with an unconfined string path. This discrepancy between path resolution checks and file creation allows an attacker to escape directory confinement, overwrite root-owned host files, and achieve host root code execution.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00717 54th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed LXD (Canonical): 4.0.13, 5.0.9, 5.21.7 +1

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
CanonicalLXD4.0.0 to before 4.0.13; 5.0.0 to before 5.0.9; 5.21.0 to before 5.21.7; 6.0 to before 6.104.0.13, 5.0.9, 5.21.7, 6.10Patch availableCNA
  • LXD VendorCanonical Affected 4.0.0 to before 4.0.13; 5.0.0 to before 5.0.9; 5.21.0 to before 5.21.7; 6.0 to before 6.10 Fixed in 4.0.13, 5.0.9, 5.21.7, 6.10 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:canonical:lxd:*:*:*:*:*:*:*:*before 4.0.13; 5.0.0 to before 5.0.9; 5.1 to before 5.21.7; 6.0 – 6.9VulnerableCanonical
  • cpe:2.3:a:canonical:lxd:*:*:*:*:*:*:*:* Versions before 4.0.13; 5.0.0 to before 5.0.9; 5.1 to before 5.21.7; 6.0 – 6.9 Vulnerable ·Canonical

Remediation

  • Fix · CNA LXD (Canonical) Fixed in 4.0.13, 5.0.9, 5.21.7, 6.10

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-66897

References

Exploit 1

  • TI-2026-22659 Authenticated RCE via unsanitized compression_algorithm CVSS 4.0CRITICAL 9.4
  • TI-2026-47475 Path traversal via unvalidated instance name in backup tarball restore enables root file write / RCE CVSS 3.1CRITICAL 9.9
  • TI-2026-45146 Cross-project instance move bypasses all project restrictions allowing host command execution CVSS 3.1CRITICAL 9.9
  • TI-2026-45143 Cross-project instance copy bypasses target project restrictions via TOCTOU in config merge CVSS 3.1CRITICAL 9.9
  • TI-2026-45142 Project restriction bypass via instance migration config override CVSS 3.1CRITICAL 9.9
  • TI-2026-45140 Root RCE via image backup.yaml symlink CVSS 3.1CRITICAL 9.9
See all 34 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences