| Package | Affected versions | Patched versions |
|---|---|---|
| github.com/rancher/rancher | ≥ 2.10.0, < 2.10.9≥ 2.11.0, < 2.11.5≥ 2.12.0, < 2.12.1≥ 2.9.0, < 2.9.11< 0.0.0-20250813072957-aee95d4e2a41 | 2.10.92.11.52.12.12.9.110.0.0-20250813072957-aee95d4e2a41 |
A vulnerability has been identified within Rancher Manager in which it did not enforce request body size limits on certain public (unauthenticated) and authenticated API endpoints. This allows a malicious user to exploit this by sending excessively large payloads, which are fully loaded into memory during processing. This could result in:
/v3-public/* endpoints, the absence of request body size limits also affected several authenticated APIs, broadening the potential attack surface. It's worth noting that other areas in Rancher do implement safeguards: requests proxied to Kubernetes APIs are subject to built-in size limits enforced by the Kubernetes API server itself, and Norman-based endpoints parse input with predefined size caps. However, the absence of similar protections in other Rancher APIs increased the risk of denial-of-service (DoS) scenarios in certain contexts.By sending large binary or text payloads to vulnerable endpoints, a malicious actor could disrupt Rancher’s availability, impacting both administrative and user operations across managed clusters.
Please consult the associated MITRE ATT&CK - Technique - Network Denial of Service for further information about this category of attack.
This vulnerability is addressed by adding a default limit of 1MiB and a setting in case this value needs to be increased.
Patched versions of Rancher include releases v2.12.1, v2.11.5, v2.10.9 and v2.9.12.
If you can't upgrade to a fixed version, please make sure that you are manually setting the request body size limits. For example, using nginx-ingress controller and only allowing requests via the ingress. For reference on how to configure the limit manually, please consult the Knowledge Base.
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