Summary
When authenticating with client_id and client_secret to an OAuth provider, authentik creates a service account for the provider. In previous authentik versions, authentication for this account was possible even when the account was deactivated. Other permissions are correctly applied and federation with other providers still take assigned policies correctly into account.
Workarounds
You can add a policy to your application that explicitly checks if the service account is still valid, and deny access if not.
return request.user.is_active
For more information
If you have any questions or comments about this advisory:
- Email us at [email protected].
Impact
CVE-2025-64521 has a CVSS score of 4.8 (Medium). The vector is network-reachable, high privileges required, and user interaction required. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (0.0.0-20251119140106-9dbdfc3f1be0); upgrading removes the vulnerable code path.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
Remediation advice
authentik 2025.8.5 and 2025.10.2 fix this issue, for other versions the workaround below can be used.
Frequently Asked Questions
- What is CVE-2025-64521? CVE-2025-64521 is a medium-severity security vulnerability in goauthentik.io (go), affecting versions < 0.0.0-20251119140106-9dbdfc3f1be0. It is fixed in 0.0.0-20251119140106-9dbdfc3f1be0.
- How severe is CVE-2025-64521? CVE-2025-64521 has a CVSS score of 4.8 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
- Which versions of goauthentik.io are affected by CVE-2025-64521? goauthentik.io (go) versions < 0.0.0-20251119140106-9dbdfc3f1be0 is affected.
- Is there a fix for CVE-2025-64521? Yes. CVE-2025-64521 is fixed in 0.0.0-20251119140106-9dbdfc3f1be0. Upgrade to this version or later.
- Is CVE-2025-64521 exploitable, and should I be worried? Whether CVE-2025-64521 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2025-64521 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2025-64521? Upgrade
goauthentik.ioto 0.0.0-20251119140106-9dbdfc3f1be0 or later.