GHSA-h6xx-pmxh-3wgp go.etcd.io/etcd Authentication Bypass

• Go go.etcd.io/etcd/v3: >= 3.2.0, < 3.2.26 → fixed in 3.2.26 • Go go.etcd.io/etcd/v3: >= 3.3.0, < 3.3.11 → fixed in 3.3.11 • Go go.etcd.io/etcd: < 0.5.0-alpha.5.0.20190108173120-83c051b701d3 → fixed in 0.5.0-alpha.5.0.20190108173120-83c051b701d3

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.