authentik: Non-admin user can retrieve confidential OAuth client_secret via /api/v3/oauth2/access_tokens/_CVE-2026-40166

{
    "lastseen": "",
    "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.",
    "published": "2026-05-22T18:52:46.650Z",
    "modified": "2026-05-22T18:52:46.650Z",
    "type": "cve",
    "title": "authentik: Non-admin user can retrieve confidential OAuth client_secret via /api/v3/oauth2/access_tokens/",
    "source": "GitHub_M",
    "references": "https://github.com/goauthentik/authentik/security/advisories/GHSA-hhpc-rqgm-pxj4\nhttps://github.com/goauthentik/authentik/releases/tag/version%2F2025.12.5\nhttps://github.com/goauthentik/authentik/releases/tag/version%2F2026.2.3",
    "id": "CVE-2026-40166",
    "bulletinFamily": "",
    "cwe": [
        "CWE-200",
        "CWE-863"
    ],
    "cvelist": null,
    "sourceData": "goauthentik authentik < 2025.12.5\ngoauthentik authentik >= 2026.2.0-rc1, < 2026.2.3",
    "sourceHref": "",
    "cvss": {
        "score": 7.1,
        "severity": "HIGH",
        "vector": "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",
        "version": "4.0"
    },
    "cvss2": [],
    "cvss3": {
        "version": "",
        "vectorString": "",
        "baseScore": 0,
        "baseSeverity": "",
        "attackVector": "",
        "attackComplexity": "",
        "privilegesRequired": "",
        "userInteraction": "",
        "scope": "",
        "confidentialityImpact": "",
        "integrityImpact": "",
        "availabilityImpact": "",
        "cvssV3": {
            "version": "",
            "vectorString": "",
            "baseScore": 0,
            "baseSeverity": "",
            "attackVector": "",
            "attackComplexity": "",
            "privilegesRequired": "",
            "userInteraction": "",
            "scope": "",
            "confidentialityImpact": "",
            "integrityImpact": "",
            "availabilityImpact": ""
        }
    },
    "href": "",
    "category_name": "CVE",
    "post_link": "",
    "product": "authentik",
    "version": "< 2025.12.5",
    "vendor": "goauthentik",
    "ai_description": "",
    "ai_severity": "",
    "ai_vendor": "",
    "ai_product": "",
    "ai_version": "",
    "ai_score": 0
}