CVE-2024-23647 (GCVE-0-2024-23647)
Vulnerability from cvelistv5 – Published: 2024-01-30 16:10 – Updated: 2025-06-17 21:29
VLAI
EPSS
VEX
Title
PKCE downgrade attack in Authentik
Summary
Authentik is an open-source Identity Provider. There is a bug in our implementation of PKCE that allows an attacker to circumvent the protection that PKCE offers. PKCE adds the code_challenge parameter to the authorization request and adds the code_verifier parameter to the token request. Prior to 2023.8.7 and 2023.10.7, a downgrade scenario is possible: if the attacker removes the code_challenge parameter from the authorization request, authentik will not do the PKCE check. Because of this bug, an attacker can circumvent the protection PKCE offers, such as CSRF attacks and code injection attacks. Versions 2023.8.7 and 2023.10.7 fix the issue.
Severity
6.5 (Medium)
SSVC
Exploitation: none
Automatable: no
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2024-01-31 17:22 UTC
CWE
- CWE-287 - Improper Authentication
Assigner
GitHub_M
CNA
References
2 references
| URL | Tags |
|---|---|
| https://github.com/goauthentik/authentik/security… | x_refsource_CONFIRM |
| https://github.com/goauthentik/authentik/commit/3… | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| goauthentik | authentik |
Affected:
< 2023.8.7
Affected: >= 2023.10.0, < 2023.10.7 |
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