Description
An authorization bypass vulnerability in LXD due to a timing flaw during configuration merging allows an authenticated attacker to bypass target project restrictions during cross-project instance copies. When copying an instance to a target project, LXD performs restriction checks before configuration merging is complete, creating a time-of-check to time-of-use (TOCTOU) condition. An attacker can exploit this flaw to copy instances with disallowed high-privilege configurations into restricted projects, bypassing security controls.
Affected products
canonical: lxd
References2
- github.com/canonical/lxd/security/advisories/GHSA-v989-qw7w-xvg4 Vendor AdvisoryExploitMitigation
- github.com/canonical/lxd/security/advisories/GHSA-v989-qw7w-xvg4 Vendor AdvisoryExploitMitigation
Metrics
- CVSS 3.1
-
9.9
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 28 · as of 12 November 2026
- CWE
- CWE-367CWE-863
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