Paper/Archive/CVE-2026-63300

CVE-2026-63300

Canonical LXD — Cross-project instance move bypasses all project restrictions allowing host command execution

Description · from the CVE record

An improper validation vulnerability in the instancePostMigration function in lxd/instance_post.go of LXD allows an authenticated attacker with can_create_instances permissions on a restricted project to bypass project-level security restrictions. When migrating an instance between projects, LXD fails to validate the instance's configuration against the target project's enforced restrictions (such as restricted.containers.lowlevel, restricted.devices.*, and restricted.networks.access). An attacker can exploit this by creating a disallowed or high-privilege instance in an unrestricted project and subsequently moving it into the restricted project.

Affected

ProductAffectedFixed inSource
LXD5.0.0 – < 5.0.85.0.8CNA
LXD5.21.0 – < 5.21.65.21.6CNA
LXD6.0 – < 6.106.10CNA

Scores by source

canonical (CNA)9.9CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
CISA ADPSSVCExploitation: poc · Automatable: no · Technical impact: total

References

advisorygithub.com/canonical/lxd/security/advisories/GHSA-5g5r-wh97-qcq2patchgithub.com/canonical/lxd/pull/18651patchgithub.com/canonical/lxd/pull/18605