CVE-2023-48228 OAuth2: PKCE can be fully circumvented
Attackers can bypass PKCE protection in OAuth2 flows by omitting the code verifier, potentially leading to unauthorized access.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2023-48228?
CVE-2023-48228 is a high-severity authentication bypass vulnerability in goauthentik authentik, published on 21 Nov 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
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.
Weakness: CWE-287
Which versions are affected by CVE-2023-48228?
1 open source package ship an affected version, including authentik. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
authentik Bitnami | All versions | 2023.8.5, 2023.10.4 |
Products include Goauthentik Authentik.
How do I fix CVE-2023-48228?
Upgrade authentik to a fixed version for your release line: 2023.8.5 or 2023.10.4.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2023-48228 being exploited?
There is no known exploitation of CVE-2023-48228 in the wild and no public exploit code.
Other vulnerabilities in goauthentik authentik
- CVE-2026-49448 authentik: SourceStage bypass via empty POST
- CVE-2023-46249 authentik potential installation takeover when default admin user is deleted
- CVE-2022-23555 authentik vulnerable to Improper Authentication via invitation URL token reuse
- CVE-2026-42849 authentik: Reflected XSS in SFE AutosubmitStage allows IDP account takeover
- CVE-2026-25227 authentik affected by Remote Code Execution via Context Key Injection in PropertyMapping Test Endpoint
Sources
Also known as BIT-authentik-2023-48228, GHSA-fm34-v8xq-f2c3.