Local Incus UI web server vulnerable to nuthentication bypass (lxc incus)
At a glance
- Source
- NVD
- EPSS
- EPSS 0.35 % · percentile 29 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- GitHub_M
- NVD status
- Analyzed
Description
Incus is a system container and virtual machine manager. Prior to version 6.23.0, the web server spawned by `incus webui` incorrectly validates the authentication token such that an invalid value will be accepted. `incus webui` runs a local web server on a random localhost port. For authentication, it provides the user with a URL containing an authentication token. When accessed with that token, Incus creates a cookie persisting that token without needing to include it in subsequent HTTP requests. While the Incus client correctly validates the value of the cookie, it does not correctly validate the token when passed int the URL. This allows for an attacker able to locate and talk to the temporary web server on localhost to have as much access to Incus as the user who ran `incus webui`. This can lead to privilege escalation by another local user or an access to the user's Incus instances and possibly system resources by a remote attack able to trick the local user into interacting with the Incus UI web server. Version 6.23.0 patches the issue.
Weaknesses (CWE)
- CWE-287 — Improper Authentication
References
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | HIGH 8.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H | GitHub_M |
| CVSS 3.1 | HIGH 8.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H | NVD · security-advisories@github.com (Secondary) |
Advisories
- GHSA-453r-g2pg-cxxq — Local Incus UI web server vulnerable to nuthentication bypass
- GO-2026-4879 — Local Incus UI web server vulnerable to nuthentication bypass in github.com/lxc/incus
European references
- ENISA EUVD · EUVD-2026-16490
- GCVE · GCVE-0-2026-33898
Affected configurations (NVD CPE)
cpe:2.3:a:linuxcontainers:incus:*:*:*:*:*:*:*:*< 6.23.0
Affected products
| Product | Versions |
|---|---|
| lxc · incus | affected < 6.23.0 |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |