CVE-2026-63297
CriticalCVSS 9.9Summary
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. LXD performs restriction checks before configuration merging is complete, creating a time-of-check to time-of-use (TOCTOU) condition.
Risk Assessment
An attacker can copy instances with disallowed high-privilege configurations into restricted projects, bypassing security controls.
Recommendation
Upgrade LXD to a patched version that eliminates the TOCTOU condition and review instance copy processes.
Original NVD description (English source)
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.