Security approach
A detailed overview of how customer, subscriber and inquiry data is protected throughout CodeKits.shop, informed by Jonathan's cybersecurity studies and secure-development practice.
Sensitive personal fields are encrypted before MySQL storage with AES-256-GCM. Each value receives a fresh cryptographically random 96-bit nonce and a 128-bit authentication tag. GCM provides confidentiality and integrity: altered ciphertext fails authentication rather than silently producing changed data.
HKDF-SHA-256 derives different encryption and lookup keys for each data purpose. The master key is kept outside the source code in restricted server configuration and must be backed up separately from the database. Versioned ciphertext supports controlled future changes, but key rotation and recovery still require tested operational procedures.
Purchase, download and inquiry tables avoid readable personal fields where possible. They retain a pseudonymous marker while encrypted values are separated into a protected personal-data table. Keyed one-way hashes support record association without exposing the original identifier in normal database views.
Stripe Checkout handles card details, so CodeKits.shop does not store raw card numbers or card security codes. Stripe webhooks are signature-verified. Download links use cryptographically random tokens, while only token hashes are stored, and links have expiry and usage limits.
Email subscriptions retain only the encrypted email, consent record and unsubscribe credential. Product downloads retain the encrypted buyer record, licence and fulfilment status, usage count and broad regional totals.
The normal subscriber dashboard does not decrypt or display email addresses. It shows a short pseudonymous fingerprint with consent and status information. When a newsletter is sent, a protected server-only mailing route decrypts active recipients in memory for delivery through the authenticated email provider. A server operator who also controls the encryption key could technically decrypt the records, so access control and key separation remain essential.
The application uses parameterized MySQL queries, server-only secrets, input length limits, rate limiting, bot traps, secure production builds and HTTPS deployment behind Nginx. Email transport uses authenticated SMTP over TLS when configured. Administrative mailbox security and server patching remain important parts of the overall system.
No online system or encryption method can responsibly be described as perfectly secure or unbreakable. CodeKits.shop uses strong current controls, minimises collected data, reviews dependencies and documents limitations. Security must be maintained through updates, access control, monitoring, backups and tested incident response.
Responsible disclosure and security questions can be sent to [email protected].
