Canonical LXD up to 4.0.11/5.0.3/5.21.1/6.0 Backup Import path traversal

Summaryinfo

A vulnerability was found in Canonical LXD up to 4.0.11/5.0.3/5.21.1/6.0. It has been rated as very critical. This vulnerability affects unknown code of the component Backup Import. The manipulation leads to path traversal. This vulnerability is traded as CVE-2026-66898. It is possible to initiate the attack remotely. There is no exploit available.

Detailsinfo

A vulnerability was found in Canonical LXD up to 4.0.11/5.0.3/5.21.1/6.0. It has been rated as very critical. This issue affects an unknown function of the component Backup Import. The manipulation with an unknown input leads to a path traversal vulnerability. Using CWE to declare the problem leads to CWE-22. The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

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.

The advisory is shared at github.com. The identification of this vulnerability is CVE-2026-66898 since 07/28/2026. The exploitation is known to be easy. The attack may be initiated remotely. Additional levels of successful authentication are needed for exploitation. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 08/12/2026). MITRE ATT&CK project uses the attack technique T1006 for this issue.

Upgrading to version 4.0.12, 5.0.4, 5.21.2 or 6.1 eliminates this vulnerability.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Vendor

• Canonical

Name

• LXD

Version

• 4.0.0
• 4.0.1
• 4.0.2
• 4.0.3
• 4.0.4
• 4.0.5
• 4.0.6
• 4.0.7
• 4.0.8
• 4.0.9
• 4.0.10
• 4.0.11
• 5.0.0
• 5.0.1
• 5.0.2
• 5.0.3
• 5.21.0
• 5.21.1
• 6.0

License

• open-source

Website

• Product: https://github.com/canonical/lxd/

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Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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