CVE-2024-23647
MEDIUMCVE-2024-23647 is a medium-severity (CVSS 6.5) Improper Authentication vulnerability in goauthentik.io. O3 Security confirms whether CVE-2024-23647 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
PKCE downgrade attack in Authentik
Blast Radius
goauthentik.io🐹goauthentik.ioReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
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.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | goauthentik.io | ≥ 2023.10.0&&< 2023.10.7 | 2023.10.7 |
| 🐹Go | goauthentik.io | all versions | 2023.8.7 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for goauthentik.io. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update goauthentik.io to 2023.10.7 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2024-23647 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2024-23647 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2024-23647. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2024-23647 in your dependencies?
O3 detects CVE-2024-23647 across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.