Canonical LXD up to 4.0.11/5.0.7/5.21.5/6.9 Symlink backup.yaml symlink

Summaryinfo

A vulnerability identified as very critical has been detected in Canonical LXD up to 4.0.11/5.0.7/5.21.5/6.9. This affects an unknown part of the file backup.yaml of the component Symlink Handler. The manipulation leads to symlink. This vulnerability is uniquely identified as CVE-2026-63294. The attack is possible to be carried out remotely. No exploit exists.

Detailsinfo

A vulnerability was found in Canonical LXD up to 4.0.11/5.0.7/5.21.5/6.9 and classified as very critical. This issue affects some unknown functionality of the file backup.yaml of the component Symlink Handler. The manipulation with an unknown input leads to a symlink vulnerability. Using CWE to declare the problem leads to CWE-61. The product, when opening a file or directory, does not sufficiently account for when the file is a symbolic link that resolves to a target outside of the intended control sphere. This could allow an attacker to cause the product to operate on unauthorized files. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

A link following vulnerability in LXD allows an attacker to achieve root command execution on the host system. During the import or unpacking of crafted image or backup archives, LXD fails to properly validate and confine the backup.yaml file when it exists as a symbolic link. An attacker can exploit this flaw by providing a malicious archive with a symlinked backup.yaml file, causing LXD to process unconfined configuration metadata and execute arbitrary commands with root privileges.

The advisory is shared at github.com. The identification of this vulnerability is CVE-2026-63294 since 07/16/2026. The exploitation is known to be easy. The attack may be initiated remotely. It demands that the victim is doing some kind of user interaction. Technical details are known, but no exploit is available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 08/12/2026).

Upgrading to version 4.0.12, 5.0.8, 5.21.6 or 6.10 eliminates this vulnerability.

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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
• 5.0.4
• 5.0.5
• 5.0.6
• 5.0.7
• 5.21.0
• 5.21.1
• 5.21.2
• 5.21.3
• 5.21.4
• 5.21.5
• 6.0
• 6.1
• 6.2
• 6.3
• 6.4
• 6.5
• 6.6
• 6.7
• 6.8
• 6.9

License

• open-source

Website

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

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