🛡️ CVE-2026-40166 — authentik

🟠 CVSS 8.0 — High ✅ No Known Exploit NVD
8.0
CVSS Score
0 Low4 Medium7 High9 Critical10

Description

authentik: Non-admin user can retrieve confidential OAuth client_secret via /api/v3/oauth2/access_tokens/

authentik is an open-source identity provider. In versions prior to 2025.12.5 and 2026.2.0 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.

Affected software

CVE-2026-40166 is recorded against 2 packages.

  • authentik
  • unknown

Timeline and source

Published on 1 June 2026 and last revised on 8 July 2026. No public exploit is currently recorded for this entry. Record sourced from NVD.

References

github.com (Web)
github.com (Web)
github.com (Web)
nvd.nist.gov (Web)

Details

Severity HIGH
CVSS Score 8.0
CVSS Vector N/A
CWE N/A
Public Exploit ✅ No
Source NVD
Published 2026-06-01
Updated 2026-08-12
Modified 2026-07-08
Fix URL N/A

Affected Packages

Software From version Fixed in
authentik — —
unknown — —

Similar Threats

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