Security is Elusive: How to Keep Your Data Safe at Rest and in Transit

#security

🔐 Security is Elusive: How to Keep Your Data Safe at Rest and in Transit

“There are only two types of companies: those that have been hacked, and those that will be.” — Robert Mueller, Former FBI Director

Computer security isn’t a single feature you can toggle on. It’s a moving target—vulnerabilities exist at every layer of the stack, from the silicon in your CPU to the apps your team builds. In this landscape, protecting your data—both at rest and in transit—isn’t optional. It’s foundational.

So how do you ensure your data is safe?

Let’s break it down.

💾 Data at Rest: Lock It Down

Data at rest includes anything stored—on disk, in a database, or on a backup drive. If someone gets access to your infrastructure or hardware, can they read your data? That’s the threat model.

1. Encrypt everything

  • Use modern encryption like AES-256.
  • Encrypt disks (e.g., FileVault, LUKS).
  • Encrypt data at the application level for high-risk fields (e.g., user credentials, SSNs).

2. Control access ruthlessly

  • Apply the principle of least privilege.
  • Use roles and fine-grained permissions (RBAC/ABAC).
  • Rotate credentials regularly.

3. Protect your encryption keys

  • Store keys in a managed vault (AWS KMS, HashiCorp Vault).
  • Never embed secrets in your codebase.
  • Audit key access and rotate on schedule.

4. Monitor and alert

  • Log all access to sensitive data.
  • Set up alerts for unusual access patterns (e.g., mass downloads, off-hours access).

🌐 Data in Transit: Make Eavesdropping Useless

Data in transit is anything moving across a network—between users, services, or APIs. Every time it moves, it risks exposure.

1. Use TLS. No excuses.

  • TLS 1.2 or 1.3, with strong ciphers (ECDHE + AES-GCM).
  • Enforce HTTPS on all endpoints.
  • Validate certificates to avoid MITM attacks.

2. End-to-end encryption where possible

  • For messaging apps or P2P communication (think Signal), E2E encryption ensures even your servers can’t read the data.

3. Secure internal traffic

  • Use VPNs, service meshes (like Istio), or encrypted overlay networks (like WireGuard).
  • Don’t trust the internal network by default—apply zero trust principles.

4. Watch for application-layer leaks

  • Sanitize inputs, use strict API validation, and guard against XSS, CSRF, and injection attacks.

🧱 Defense in Depth: Assume Breach

Security isn’t a single wall—it’s layers of containment.

  • Regularly patch and update your stack.
  • Segment your network. Don’t let a breach in one service spill into others.
  • Back up data securely and test your restores.
  • Train your team. Humans are still the weakest link.

✨ Bottom Line

There’s no such thing as perfect security, only risk reduction. The goal is to make successful attacks expensive, noisy, and impractical. If you're encrypting everything, controlling access, and watching for trouble, you’re well ahead of the curve.

Data at rest. Data in transit. Cover both—and sleep a little easier.