MariaDB Connector/Node.js is used to connect applications developed on Node.js to MariaDB and MySQL databases. From 3.3.0 until 3.5.4, the zero-configuration TLS fingerprint-validation path calls Ed25519PasswordAuth.hash() through Authentication.validateFingerPrint, but Ed25519PasswordAuth.hash() references a seed identifier that is not in scope. Exposure requires a MariaDB server reached over TCP, TLS enabled with ssl: true or an ssl object whose rejectUnauthorized value is not false, a password set, no ssl.ca configured, and client_ed25519 negotiated as the authentication plugin. Under those conditions, a legitimate server, malicious server, or network attacker presenting a self-signed certificate can reach this path and cause a synchronous ReferenceError to escape the socket data handler. Under Node.js default uncaught-exception behavior, the client process terminates, causing denial of service. Configurations using a provided CA, rejectUnauthorized: false, another authentication plugin, or a Unix socket do not reach this vulnerable path. This issue is fixed in version 3.5.4.

Affected: npm: mariadb

### Description On the zero-configuration TLS path, the connector accepts a self-signed server certificate at the TLS level and then validates the server's identity from the fingerprint hash the server appends to the final OK_Packet (`Authentication.validateFingerPrint`). That validation calls `hash()` on the authentication plugin in use to obtain the password-derived secret both sides combine with the seed and the certificate fingerprint.

`Ed25519PasswordAuth.hash()` referenced an identifier `seed` that was not in scope: it was neither a parameter of the method nor a module-scope binding, existing only as a parameter of the unrelated static `encryptPassword(password, seed)`. Invoking the method therefore threw `ReferenceError: seed is not defined`.

The throw happens synchronously inside the socket `data` handler, and no frame between `PacketInputStream.onData()` and the plugin guards it, so the error escapes as an uncaught exception rather than surfacing as a connection error.

Because the fingerprint hash is what a legitimate MariaDB server sends on this path, ed25519 authentication with zero-configuration TLS never completed successfully — the failure is not limited to a hostile server.

### Impact Denial of service against the client process. Under Node's default `uncaughtException` behaviour the process exits, so a long-running service is terminated rather than seeing a failed connection attempt. No credential is disclosed and no data is altered; the impact is availab…