CVE-2026-63297

Publication date 13 August 2026

Last updated 13 August 2026


Ubuntu priority

Cvss 3 Severity Score

9.9 · Critical

Score breakdown

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.

Status

Package Ubuntu Release Status
lxd 26.04 LTS resolute Not in release
24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal
Needs evaluation
18.04 LTS bionic
Needs evaluation
16.04 LTS xenial
Needs evaluation

Severity score breakdown

CVSS version: CVSS v3.0

Base score 9.9 · Critical

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H


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