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Vulnerability · Published Nov 21, 2023 · Assigned by GitHub_M

CVE-2023-48228OAuth2: PKCE can be fully circumvented

High 7.5

In plain English

A high-severity improper authentication in authentik from goauthentik. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 1.2% (higher than 69% of all known vulnerabilities).

Severity (CVSS 3.1)7.5High
Exploit odds (30 days)1.2%top 30.5% of all CVEs
Exploited in the wildNo reportsnot in CISA KEV
Attack toolingNoneno public tooling known

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.

Affected products (as reported)

VendorProductVersions
goauthentik authentik < 2023.10.4< 2023.8.5

Weakness: CWE-287 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

References