CVE-2026-63297

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.

CVSS v3 9.9 CRITICAL

9.9^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.1 / Impact : 6.0

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope CHANGED

References

Link	Resource
https://github.com/canonical/lxd/security/advisories/GHSA-v989-qw7w-xvg4	Vendor Advisory Exploit Mitigation
https://github.com/canonical/lxd/security/advisories/GHSA-v989-qw7w-xvg4	Vendor Advisory Exploit Mitigation

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:canonical:lxd::::::::
	cpe:2.3:a:canonical:lxd::::::::
	cpe:2.3:a:canonical:lxd::::::::

History

No history.

Information

Published : 2026-08-12 20:17

Updated : 2026-09-11 15:18

NVD link : CVE-2026-63297

Mitre link : CVE-2026-63297

CVE.ORG link : CVE-2026-63297

JSON object : View

Products Affected

canonical

lxd

CWE

CWE-367

Time-of-check Time-of-use (TOCTOU) Race Condition

CWE-863

Incorrect Authorization

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