Canonical LXD Security Bypass
2026-04-09
Backup import in Canonical LXD before 6.8 bypasses project security restrictions, enabling privilege escalation to full host compromise. An authenticated remote attacker with instance-creation permission in a restricted project crafts malicious backup archives containing conflicting configuration files: backup/index.yaml passes validation, while backup/container/backup.yaml (never validated) carries forbidden directives like security.privileged=true or raw.lxc commands. Exploiting this dual-file validation gap allows unrestricted container creation that breaks isolation boundaries. No public exploit identified at time of analysis.
Privilege escalation in Canonical LXD 4.12 through 6.7 enables remote authenticated restricted TLS certificate users to gain cluster admin privileges. Exploitation requires high-privilege authentication (PR:H) but no user interaction. The vulnerability stems from missing Type field validation in doCertificateUpdate function when processing PUT/PATCH requests to the certificates API endpoint. Attack scope is changed (S:C), allowing attackers to break containment and achieve full cluster compromise with high impact to confidentiality, integrity, and availability. No public exploit identified at time of analysis.
Privilege escalation in Canonical LXD 4.12-6.7 allows authenticated remote attackers with VM instance editing rights to bypass project restrictions via incomplete denylist validation. Attackers inject AppArmor rules and QEMU chardev configurations through unblocked raw.apparmor and raw.qemu.conf keys, bridging the LXD Unix socket into guest VMs. Successful exploitation enables escalation to LXD cluster administrator and subsequently to host root access. No public exploit identified at time of analysis. Authenticated remote exploitation (PR:H) with cross-scope impact on confidentiality, integrity, and availability.