To mitigate insecure TLS renegotiation vulnerabilities, implement the following strategies:

**Primary Mitigation - Enable RFC 5746 Support:**

Upgrade your TLS implementation to support RFC 5746 (TLS Renegotiation Indication Extension). Modern versions of OpenSSL, GnuTLS, and other TLS libraries include this by default.

```nginx
# Nginx configuration (OpenSSL 1.0.1+ automatically supports RFC 5746)
ssl_protocols TLSv1.2 TLSv1.3;
ssl_prefer_server_ciphers on;
```

```apache
# Apache configuration (mod_ssl with OpenSSL 1.0.1+ supports RFC 5746)
SSLProtocol -all +TLSv1.2 +TLSv1.3
SSLHonorCipherOrder on
```

**Alternative Mitigations:**

1. **Disable Renegotiation Entirely** - If your application doesn't need renegotiation, disable it completely:

```nginx
# Nginx - renegotiation disabled by default in recent versions
ssl_session_cache shared:SSL:10m;
ssl_session_timeout 10m;
```

```apache
# Apache with mod_ssl
SSLInsecureRenegotiation off
```

2. **Upgrade to TLS 1.3** - TLS 1.3 redesigned renegotiation mechanisms to be inherently secure:

```bash
# Test server configuration
openssl s_client -connect example.com:443 -tls1_3
```

**Testing and Verification:**

```bash
# Test for RFC 5746 support
openssl s_client -connect example.com:443 -reconnect

# Check for secure renegotiation indication
nmap --script ssl-enum-ciphers -p 443 example.com
```

**Java Applications:**

For Java applications, ensure you're using a JVM that supports RFC 5746:

```bash
# Java system property to require secure renegotiation
-Djdk.tls.allowLegacyResumption=false
-Djdk.tls.allowLegacyMasterSecret=false
```

**Monitoring for Attacks:**

Monitor for suspicious renegotiation patterns in your TLS logs:

```bash
# Example log analysis for unusual renegotiation activity
grep -i "renegotiation\|handshake" /var/log/nginx/error.log
```

By implementing RFC 5746 support or disabling renegotiation entirely, you eliminate the attack vector while maintaining secure TLS communications.