Vulnerability · Published Oct 22, 2026 · Assigned by GitHub_M
CVE-2026-114619Authlib: OpenID implicit grant checks raw scope instead of allowed scope before issuing ID tokens
Medium 4.6
In plain English
A medium-severity incorrect authorization in authlib from authlib. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 5% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
Authlib is a Python library which builds OAuth and OpenID Connect servers. Prior to 1.9.0, OpenIDImplicitGrant.validate_authorization_request() checks the client-controlled raw request.payload.scope for openid after the parent grant has filtered allowed scopes into request.scope. A registered client permitted an ID token response type but not the openid scope can add openid to the request, obtain user consent, and receive a signed ID token containing the user's subject and allowed profile claims. Authorization code flow and deployments that allow openid for every client permitted an ID token response are not affected. In authlib/oidc/core/grants/implicit.py, OpenIDImplicitGrant.validate_authorization_request() checks request.payload.scope instead of the filtered request.scope. This issue is fixed in version 1.9.0.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | python-authlib | no fix listed | DEBIAN-CVE-2026-114619 |
| Debian:13 | python-authlib | no fix listed | DEBIAN-CVE-2026-114619 |
| Debian:14 | python-authlib | 1.9.1-1 | DEBIAN-CVE-2026-114619 |
| PyPI | authlib | 1.9.0 | GHSA-q686-2qmg-hqc7 |
| PyPI | authlib | 1.9.0 | PYSEC-2026-4359 |
| Ubuntu:26.10 | python-authlib | no fix listed | UBUNTU-CVE-2026-114619 |
Affected products (as reported)
Weakness: CWE-863 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N
References
- https://github.com/authlib/authlib/security/advisories/GHSA-q686-2qmg-hqc7 x_refsource_CONFIRM
- https://github.com/authlib/authlib/pull/945 x_refsource_MISC
- https://github.com/authlib/authlib/commit/e3bd41cb29dcfee434453b135ffb487884baeedf x_refsource_MISC
- https://github.com/authlib/authlib/releases/tag/v1.9.0 x_refsource_MISC