GHSA-5m9f-rphj-c435

## Vulnerability Summary

`com.rabbitmq.client.TrustEverythingTrustManager` accepts ANY TLS certificate (including null chains) and is used as the default trust manager when calling `ConnectionFactory.useSslProtocol()` without arguments. Combined with hostname verification being disabled by default, this enables trivial man-in-the-middle attacks.

## Affected Components

- `com.rabbitmq.client.TrustEverythingTrustManager` — accepts any certificate - `com.rabbitmq.client.ConnectionFactory.useSslProtocol()` — uses TrustEverythingTrustManager - Hostname verification disabled by default (`enableHostnameVerification()` must be called explicitly) - `com.rabbitmq.client.ConnectionFactory.getPassword()` — returns plaintext with no redaction - Default port 5672 (plaintext) with PLAIN SASL — credentials sent unencrypted

## POC (Verified on Java 21, amqp-client 5.25.0)

```java // TrustEverythingTrustManager accepts ANY certificate including null TrustEverythingTrustManager tm = new TrustEverythingTrustManager(); tm.checkServerTrusted(null, "RSA"); // No exception — accepts null cert chain tm.getAcceptedIssuers(); // Returns empty array — trusts all CAs

// ConnectionFactory defaults ConnectionFactory factory = new ConnectionFactory(); factory.useSslProtocol(); // Uses TrustEverythingTrustManager internally // enableHostnameVerification() NOT called by default

// Credential exposure factory.setPassword("secret_password_123"); factory.getPassword(); // Returns "secret_password_123" — no redaction

// Default plaintext port factory.getPort(); // 5672 (plaintext, not 5671/TLS)

// PLAIN SASL sends cleartext credentials PlainMechanism pm = new PlainMechanism(); // handleChallenge() sends username+password in cleartext ```

## Attack Scenarios

1. **MITM**: Attacker presents self-signed cert → `TrustEverythingTrustManager` accepts it → all RabbitMQ traffic intercepted 2. **Credential theft**: Default plaintext port (5672) + PLAIN SASL = credentials readable on network 3. **DNS rebinding**: No hostname verification → attacker DNS record → MITM without cert 4. **Logging exposure**: `getPassword()` returns plaintext → credentials in logs/stack traces

## Suggested Fix 1. Deprecate `TrustEverythingTrustManager` — it should never be used in production 2. `useSslProtocol()` should use the JVM default trust store, not TrustEverything 3. Enable hostname verification by default 4. Redact password in `getPassword()` or remove the public getter 5. Warn when using PLAIN SASL without TLS