Canonical LXD up to 4.0.11/5.0.7/5.21.5/6.9 Container Isolation security.idmap.isolated authorization

Summaryinfo

A vulnerability classified as very critical has been found in Canonical LXD up to 4.0.11/5.0.7/5.21.5/6.9. Affected by this vulnerability is an unknown functionality of the component Container Isolation. The manipulation of the argument security.idmap.isolated leads to authorization. This vulnerability is listed as CVE-2026-63295. The attack may be initiated remotely. There is no available exploit.

Detailsinfo

A vulnerability was found in Canonical LXD up to 4.0.11/5.0.7/5.21.5/6.9. It has been rated as very critical. This issue affects some unknown processing of the component Container Isolation. The manipulation of the argument security.idmap.isolated with an unknown input leads to a authorization vulnerability. Using CWE to declare the problem leads to CWE-639. The system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

An authorization bypass vulnerability in LXD allows an authenticated attacker to bypass project-level container isolation restrictions. When a project is configured with restrictions on container privileges (such as enforcing restricted.containers.privilege=isolated), LXD fails to enforce the requirement if an instance configuration omits the security.idmap.isolated key. An attacker can exploit this flaw by creating or updating an instance without explicitly setting security.idmap.isolated, bypassing the target project's security constraints.

The advisory is shared at github.com. The identification of this vulnerability is CVE-2026-63295 since 07/16/2026. The exploitation is known to be easy. The attack may be initiated remotely. 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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