UBUNTU-CVE-2026-33898

Source
https://ubuntu.com/security/CVE-2026-33898
Import Source
https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-33898.json
JSON Data
https://api.osv.dev/v1/vulns/UBUNTU-CVE-2026-33898
Upstream
Published
2026-03-27T00:16:00Z
Modified
2026-05-20T16:25:30.931680526Z
Severity
  • 8.8 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H CVSS Calculator
  • Ubuntu - medium
Summary
[none]
Details

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.

References

Affected packages

Ubuntu:Pro:24.04:LTS / incus

Package

Name
incus
Purl
pkg:deb/ubuntu/incus?arch=source&distro=esm-apps%2Fnoble

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected

Affected versions

0.*
0.4-1ubuntu1
0.5.1-1
0.5.1-3
0.6-1
6.*
6.0.0-1
6.0.0-1ubuntu0.1
6.0.0-1ubuntu0.2
6.0.0-1ubuntu0.2+esm1
6.0.0-1ubuntu0.3
6.0.0-1ubuntu0.3+esm1
6.0.0-1ubuntu0.3+esm2
6.0.0-1ubuntu0.3+esm3

Ecosystem specific

{
    "binaries": [
        {
            "binary_name": "golang-github-lxc-incus-dev",
            "binary_version": "6.0.0-1ubuntu0.3+esm3"
        },
        {
            "binary_name": "incus",
            "binary_version": "6.0.0-1ubuntu0.3+esm3"
        },
        {
            "binary_name": "incus-agent",
            "binary_version": "6.0.0-1ubuntu0.3+esm3"
        },
        {
            "binary_name": "incus-client",
            "binary_version": "6.0.0-1ubuntu0.3+esm3"
        },
        {
            "binary_name": "incus-migrate",
            "binary_version": "6.0.0-1ubuntu0.3+esm3"
        },
        {
            "binary_name": "incus-tools",
            "binary_version": "6.0.0-1ubuntu0.3+esm3"
        }
    ]
}

Database specific

source
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-33898.json"

Ubuntu:25.10 / incus

Package

Name
incus
Purl
pkg:deb/ubuntu/incus?arch=source&distro=questing

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected

Affected versions

6.*
6.0.3-4
6.0.4-2

Ecosystem specific

{
    "binaries": [
        {
            "binary_name": "golang-github-lxc-incus-dev",
            "binary_version": "6.0.4-2"
        },
        {
            "binary_name": "incus",
            "binary_version": "6.0.4-2"
        },
        {
            "binary_name": "incus-agent",
            "binary_version": "6.0.4-2"
        },
        {
            "binary_name": "incus-base",
            "binary_version": "6.0.4-2"
        },
        {
            "binary_name": "incus-client",
            "binary_version": "6.0.4-2"
        },
        {
            "binary_name": "incus-extra",
            "binary_version": "6.0.4-2"
        }
    ]
}

Database specific

source
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-33898.json"

Ubuntu:26.04:LTS / incus

Package

Name
incus
Purl
pkg:deb/ubuntu/incus?arch=source&distro=resolute

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected

Affected versions

6.*
6.0.4-2
6.0.5-8

Ecosystem specific

{
    "binaries": [
        {
            "binary_name": "golang-github-lxc-incus-dev",
            "binary_version": "6.0.5-8"
        },
        {
            "binary_name": "incus",
            "binary_version": "6.0.5-8"
        },
        {
            "binary_name": "incus-agent",
            "binary_version": "6.0.5-8"
        },
        {
            "binary_name": "incus-base",
            "binary_version": "6.0.5-8"
        },
        {
            "binary_name": "incus-client",
            "binary_version": "6.0.5-8"
        },
        {
            "binary_name": "incus-extra",
            "binary_version": "6.0.5-8"
        }
    ]
}

Database specific

source
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-33898.json"