CVE-2026-40166

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Source
https://cve.org/CVERecord?id=CVE-2026-40166
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-40166.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-40166
Aliases
Published
2026-05-22T18:52:46Z
Modified
2026-08-12T03:51:40Z
Severity
  • 7.1 (High) CVSS_V4 - CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:L/SI:N/SA:N CVSS Calculator
Summary
authentik: Non-admin user can retrieve confidential OAuth client_secret via /api/v3/oauth2/access_tokens/
Details

authentik is an open-source identity provider. In versions prior to 2025.12.5 and 2026.2.0-rc1 through 2026.2.2, authenticated non-admin users with at least one OAuth2 access token can retrieve the client_secret of confidential OAuth2 providers they have previously authenticated against, exposing sensitive information to users without the correct permissions. This logic is GET /api/v3/oauth2/access_tokens/. The API response includes a nested provider object containing client_id and client_secret for providers configured with client_type: confidential, which should not be accessible to low-privilege users. This issue has been fixed in versions 2025.12.5 and 2026.2.3.

Database specific 
{
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
        "CWE-200",
        "CWE-863"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/40xxx/CVE-2026-40166.json"
}
References

Affected packages

Git / github.com/goauthentik/authentik

Affected ranges

Type
GIT
Repo
https://github.com/goauthentik/authentik
Events
Introduced
3394c17bfd5e208f8e8d53e450158e486afe575b
Fixed
5249546862986202b901c2afd860992ec48c6ef6
Database specific
Show details 
{
    "extracted_events": [
        {
            "introduced": "2026.2.0-rc1"
        },
        {
            "fixed": "2026.2.2"
        }
    ],
    "source": "DESCRIPTION"
}

Affected versions

version/2026.*
version/2026.2.0
version/2026.2.0-rc1
version/2026.2.0-rc2
version/2026.2.0-rc3
version/2026.2.0-rc4
version/2026.2.0-rc5
version/2026.2.1
version/2026.2.1-rc1
version/2026.2.2-rc1
version/2026.2.2-rc2
version/2026.2.2-rc3

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-40166.json"