{"api_version":"1","generated_at":"2026-07-31T21:12:40+00:00","cve":"CVE-2026-40166","urls":{"html":"https://cve.report/CVE-2026-40166","api":"https://cve.report/api/cve/CVE-2026-40166.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-40166","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-40166"},"summary":{"title":"authentik: Non-admin user can retrieve confidential OAuth client_secret via /api/v3/oauth2/access_tokens/","description":"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.","state":"PUBLISHED","assigner":"GitHub_M","published_at":"2026-05-22 19:17:03","updated_at":"2026-07-23 16:10:00"},"problem_types":["CWE-200","CWE-863","CWE-200 CWE-200: Exposure of Sensitive Information to an Unauthorized Actor","CWE-863 CWE-863: Incorrect 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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.","Type":"Description","Title":"authentik: Non-admin user can retrieve confidential OAuth client"}]}}}