CVE-2026-62420

Awaiting Analysis Awaiting Analysis - Queue

Authorization Bypass in LXD During Cross-Project Instance Migrations

Publication date: 2026-08-12

Last updated on: 2026-08-28

Assigner: Canonical Ltd.

Description

An authorization bypass vulnerability in LXD allows an authenticated attacker to bypass target project security restrictions during cross-project instance migrations. When moving an instance cross-project to a different cluster member via POST /1.0/instances/{name} with migration: true, project: <target>, and target: <member>, the destination node skips all project restriction checks because the request arrives as an internal cluster notification. An attacker can exploit this to introduce disallowed instance configurations into a restricted project.

CVSS Scores

EPSS Scores

Probability:
Percentile:

Meta Information

Published

2026-08-12

Last Modified

2026-08-28

Generated

2026-09-02

AI Q&A

2026-08-13

EPSS Evaluated

2026-09-01

NVD

CVE-2026-62420

EUVD

EUVD-2026-57415

Affected Vendors & Products

Vendor	Product	Version / Range
ubuntu	lxd	*
canonical	lxd	5.0
canonical	lxd	to 6.9 (exc)

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-863	The product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check.

Attack-Flow Graph

Executive Summary

CVE-2026-62420 is an authorization bypass in LXD that allows an authenticated attacker to bypass project security restrictions during cross-project instance migrations. When moving an instance between projects on different cluster members, the destination node skips project restriction checks because the request is treated as an internal cluster notification. This enables attackers to introduce disallowed instance configurations into restricted projects.

Detection Guidance

Check LXD instance migration logs for cross-project moves with migration: true and target: <member> flags. Look for instances moved into restricted projects without proper validation. Review cluster notification logs for unexpected internal transfers between projects.

Impact Analysis

An attacker with project-level access could exploit this to execute arbitrary commands as root on the host, bypassing all project restrictions. This could lead to unauthorized access, data breaches, or system compromise. The high CVSS score of 9.9 indicates severe impacts on confidentiality, integrity, and availability.

Compliance Impact

This vulnerability could lead to unauthorized access or data breaches, which may violate compliance requirements under GDPR, HIPAA, or other regulations. Failure to address it may result in legal penalties, reputational damage, and loss of trust due to compromised data integrity and confidentiality.

Mitigation Strategies

Upgrade LXD to a patched version (5.0.1+ or 6.9.1+) addressing CVE-2026-62420.
Disable cross-project instance migrations until patched, especially between cluster members.
Audit existing instances for unauthorized project assignments or configurations.
Monitor project restrictions and validate all migration requests manually.

Hi! I’m here to help you understand CVE-2026-62420. Ask me anything about the vulnerability, its impact, or mitigation strategies.

0/70