Vulnerable Components with Mutual Tls

Remediation focuses on replacing or hardening the vulnerable components rather than trying to "fix" the API logic itself. Below are language‑specific examples that address the most common findings.

1. Update the TLS library

Always run a recent, actively maintained version of OpenSSL, BoringSSL, or the language‑specific TLS stack.

# Ubuntu/Debian – ensure OpenSSL ≥ 3.0.8
sudo apt-get update
sudo apt-get install --only-upgrade openssl
# Verify
openssl version

In Go, the standard library tracks the system OpenSSL; updating the OS package is sufficient. In Node.js, ensure you are using Node ≥ 18, which bundles OpenSSL 3.0.

2. Enforce strong protocol versions and cipher suites

Configure the server (or client) to reject TLS 1.0/1.1 and weak ciphers.

# Go tls.Config example
conf := &tls.Config{
    MinVersion: tls.VersionTLS12,
    CurveID:    []tls.CurveID{tls.X25519, tls.CurveP256},
    PreferServerCipherSuites: true,
    CipherSuites: []uint16{
        tls.TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384,
        tls.TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384,
        tls.TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256,
        tls.TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256,
    },
    ClientAuth: tls.RequireAndVerifyClientCert,
    ClientCAs:  caPool, // load your trusted CA bundle
}
ln, _ := tls.Listen("tcp", ":8443", conf)

# Node.js tls.createServer example
const tls = require('tls');
const fs = require('fs');

const options = {
  key: fs.readFileSync('server-key.pem'),
  cert: fs.readFileSync('server-cert.pem'),
  ca: fs.readFileSync('ca.pem'),
  requestCert: true,
  rejectUnauthorized: true, // enforce client cert validation
  minVersion: 'TLSv1.2',
  ciphers: 'TLS_AES_256_GCM_SHA384:TLS_CHACHA20_POLY1305_SHA256',
  honorCipherOrder: true,
};

const server = tls.createServer(options, (socket) => {
  socket.write('welcome\n');
  socket.end();
});

server.listen(8443);

3. Enable certificate revocation checking

When possible, turn on OCSP stapling on the server and require OCSP validation on the client.

# NGINX example for OCSP stapling
ssl_stapling on;
ssl_stapling_verify on;
resolver 8.8.8.8 8.8.4.4 valid=300s;
resolver_timeout 5s;

In Java (SSLEngine), enable revocation checking via the PKIX parameters:

PKIXBuilderParameters pkixParams = new PKIXBuilderParameters(trustStore, new X509CertSelector());
pkixParams.setRevocationEnabled(true);
TrustManagerFactory tmf = TrustManagerFactory.getInstance("PKIX");
tmf.init(new CertParameters(pkixParams));
SSLContext ctx = SSLContext.getInstance("TLSv1.2");
ctx.init(null, tmf.getTrustManagers(), new SecureRandom());

4. Validate hostname/IP in client certificates

Ensure the server checks that the presented certificate’s SAN matches the expected client identity.

# Go – custom verification
conf := &tls.Config{
    ClientAuth: tls.RequireAndVerifyClientCert,
    VerifyPeerCertificate: func(rawCerts [][]byte, verifiedChains [][]*x509.Certificate) error {
        if len(rawCerts) == 0 {
            return errors.New("no client certificate provided")
        }
        cert, _ := x509.ParseCertificate(rawCerts[0])
        if !cert.IsCA && cert.Subject.CommonName != "expected-client" {
            return fmt.Errorf("unexpected client CN: %s", cert.Subject.CommonName)
        }
        // optionally check SAN
        return nil
    },
}

By applying these fixes, the vulnerable components are removed or mitigated, and the mTLS channel regains its intended confidentiality and authentication guarantees. middleBrick will continue to detect any regression; users can schedule regular scans via the Dashboard, CLI, or GitHub Action to maintain a strong security posture over time.