9.9Critical

Canonical Lxd

CVE-2026-62420

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: , and target: , 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.

What this means for your business

  • It affects Canonical Lxd. It matters if your company, or a supplier that handles your data, runs it.
  • Code showing how to exploit it has been published, but real attacks have not been confirmed.
  • An attacker can use it remotely, over a network, with an ordinary user login, and without anyone at your company clicking anything.
  • FIRST's prediction model gives it a 0.4% chance of attack attempts being seen in the next 30 days, ranking above 30% of all known flaws.

What to do

  1. 1Check whether your company or your suppliers run Canonical Lxd, and which version. The affected versions are listed further down this page.
  2. 2If you do, apply the vendor's fix. A patch or vendor advisory has been published.

Not sure if your company is exposed?

Fastnexa’s certified penetration testers can check whether attackers could use this flaw, or others like it, against your websites, apps and network. The full test is free for our first 10 founding clients until 31 December 2026.

Scoring

CVSS
9.9 (v3.1)
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Weakness
CWE-863
Assigned by
security@ubuntu.com

Dates

Published
2026-08-12
Last modified
2026-09-11
Sources
NVD

Affected products

  • Canonical Lxd5.0.0 - 5.0.8, 5.1 - 5.21.6, 6.0 - 6.10

As listed in the NVD configuration data. Not a statement about your estate.

References