CVE-2025-23388

Rancher allows an unauthenticated stack overflow in /v3-public/authproviders API

Workarounds

There are no workarounds for this issue. Users are recommended to upgrade, as soon as possible, to a version of Rancher Manager that contains the fix.

References

If you have any questions or comments about this advisory:

• Reach out to the SUSE Rancher Security team for security related inquiries.
• Open an issue in the Rancher repository.
• Verify with our support matrix and product support lifecycle.

An unauthenticated stack overflow crash, leading to a denial of service (DoS), was identified in Rancher’s /v3-public/authproviders public API endpoint. A malicious user could submit data to the API which would cause the Rancher server to crash, but no malicious or incorrect data would actually be written in the API. The downstream clusters, i.e., the clusters managed by Rancher, are not affected by this issue.

This vulnerability affects those using external authentication providers as well as Rancher’s local authentication.

CVE-2025-23388 has a CVSS score of 8.2 (High). The vector is network-reachable, no privileges required, and no user interaction. 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 (2.8.13, 2.9.7, 2.10.3); upgrading removes the vulnerable code path.

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The patch includes the removal of unnecessary HTTP methods of the specific API.

Patched versions include releases v2.8.13, v2.9.7 and v2.10.3.

1. What is CVE-2025-23388? CVE-2025-23388 is a high-severity security vulnerability in github.com/rancher/rancher (go), affecting versions >= 2.8.0, < 2.8.13. It is fixed in 2.8.13, 2.9.7, 2.10.3.
2. How severe is CVE-2025-23388? CVE-2025-23388 has a CVSS score of 8.2 (High). 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.
3. Which versions of github.com/rancher/rancher are affected by CVE-2025-23388? github.com/rancher/rancher (go) versions >= 2.8.0, < 2.8.13 is affected.
4. Is there a fix for CVE-2025-23388? Yes. CVE-2025-23388 is fixed in 2.8.13, 2.9.7, 2.10.3. Upgrade to this version or later.
5. Is CVE-2025-23388 exploitable, and should I be worried? Whether CVE-2025-23388 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
6. What actually determines whether CVE-2025-23388 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.
7. How do I fix CVE-2025-23388?
   • Upgrade github.com/rancher/rancher to 2.8.13 or later
   • Upgrade github.com/rancher/rancher to 2.9.7 or later
   • Upgrade github.com/rancher/rancher to 2.10.3 or later

Other vulnerabilities in github.com/rancher/rancher