CVE-2023-48228: Goauthentik Authentik

Critical severity, CVSS 9.8. EPSS: 1.2% chance of exploitation in the next 30 days.

authentik is an open-source identity provider. When initialising a oauth2 flow with a `code_challenge` and `code_method` (thus requesting PKCE), the single sign-on provider (authentik) must check if there is a matching and existing `code_verifier` during the token step. Prior to versions 2023.10.4 and 2023.8.5, authentik checks if the contents of `code_verifier` is matching only when it is provided. When it is left out completely, authentik simply accepts the token request with out it; even when the flow was started with a `code_challenge`. authentik 2023.8.5 and 2023.10.4 fix this issue.

Affected products

• Goauthentik Authentik: before 2023.8.5 (fixed in 2023.8.5); from 2023.10.0, before 2023.10.4 (fixed in 2023.10.4)

Published 2023-11-21. Last modified 2026-06-17.