CVE-2026-9640: LXD Snapshot Import Privilege Escalation Vulnerability

Severity: high (CVSS 7.2 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.6% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2026-06-26 · updated 2026-10-25
Weakness: CWE-863

Description

A privilege escalation vulnerability exists in LXD from 6.0 before 6.9, 5.21.0 before 5.21.5, and 5.0.0 before 5.0.7 regarding the handling of project-restriction policies during snapshot restoration.. An authenticated project operator in a restricted multi-tenant environment can bypass policy restrictions by importing a maliciously crafted instance backup containing restricted configuration keys within a snapshot. When the snapshot is restored, these restricted keys are applied to the live instance without policy validation. Starting the modified instance grants the operator unauthorized host root access.

Affected products

Canonical LXD: from 4.12 before 5.0.7; from 5.21.0 before 5.21.5; from 6.0 before 6.9 — fixed in 5.0.7, 5.21.5, 6.9

How to fix

Upgrade to a fixed version: Canonical LXD 5.0.7, 5.21.5, 6.9. Check the vendor advisory for mitigations.

References

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