cyberstrikeus 3.1.3 Bootstrap token authentication should not be used for users (Manual)
Profile Applicability
- Level 1 - Master Node
Description
Kubernetes provides bootstrap tokens which are intended for use by new nodes joining the cluster
These tokens are not designed for use by end-users they are specifically designed for the purpose of bootstrapping new nodes and not for general authentication
Rationale
Bootstrap tokens are not intended for use as a general authentication mechanism and impose constraints on user and group naming that do not facilitate good RBAC design. They also cannot be used with MFA resulting in a weak authentication mechanism being available.
Impact
External mechanisms for authentication generally require additional software to be deployed.
Audit
Review user access to the cluster and ensure that users are not making use of bootstrap token authentication.
Remediation
Alternative mechanisms provided by Kubernetes such as the use of OIDC should be implemented in place of bootstrap tokens.
Default Value
Bootstrap token authentication is not enabled by default and requires an API server parameter to be set.
CIS Controls
| Controls Version | Control | IG 1 | IG 2 | IG 3 |
|---|---|---|---|---|
| v8 | 6.2 Establish an Access Revoking Process | X | X | X |
| v7 | 16.7 Establish Process for Revoking Access | X | X |