etcd versions 3.2.x before 3.2.26 and 3.3.x before 3.3.11 are vulnerable to an improper authentication issue when role-based access control (RBAC) is used and client-cert-auth is enabled. If an etcd client server TLS certificate contains a Common Name (CN) which matches a valid RBAC username, a remote attacker may authenticate as that user with any valid (trusted) client certificate in a REST API request to the gRPC-gateway.
When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Etcd | Etcd | 3.2.0 (including) | 3.2.26 (excluding) |
| Etcd | Etcd | 3.3.0 (including) | 3.3.11 (excluding) |
| Red Hat Enterprise Linux 7 Extras | RedHat | etcd-0:3.2.26-1.el7 | * |
| Etcd | Ubuntu | bionic | * |
| Etcd | Ubuntu | cosmic | * |
| Etcd | Ubuntu | disco | * |
| Etcd | Ubuntu | esm-apps/bionic | * |
| Etcd | Ubuntu | upstream | * |