Implementing Personal Data Encryption on Your Website

When a database leaks, an attacker gets an SQL dump with thousands of rows — INN, passports, medical records. If data is stored in plaintext, it's a disaster: fines under 152-FZ up to 500,000 rubles, or under GDPR up to 4% of global annual turnover. The cost of a data breach averages $3.86 million globally (IBM Cost of a Data Breach Report 2022). Application-level encryption is the only way to devalue data for an attacker. Even if they get the database, without the keys the ciphertext is useless. We implement encryption in projects with high security requirements: fintech, medtech, gov. In 5 years on the market, we have completed over 30 projects for personal data protection. Our engineers hold CISSP certifications, and we guarantee compliance with 152-FZ and GDPR. We will audit your system in 2-3 days.

Let me give a real-world example from our practice: encryption in a medical CRM with 50,000 patients.

Why Encrypt Data at the Application Level?

Database-level encryption (TDE) does not protect against DBAs or SQL injections. The application itself manages keys: data is encrypted before writing and decrypted only by authorized queries. This provides granular access control and isolates data from the infrastructure.

Data Encryption vs Hashing

Data to Encrypt

• INN, SNILS, passport series/number
• Medical data, diagnoses
• Financial data, card numbers (PCI DSS requires a separate approach)
• Biometrics

Data to Hash

• Passwords → bcrypt, Argon2id
• Secret tokens, API keys

For searching encrypted fields, we use deterministic encryption or tokenization — more on that later.

Choosing an Algorithm: AES-256-GCM vs ChaCha20-Poly1305

AES-256-GCM is the standard for encrypting data at rest. With AES-NI, it is 3x faster than ChaCha20-Poly1305. If the server lacks AES-NI support, ChaCha20-Poly1305 is a reliable alternative. RSA-OAEP is used for encrypting keys or when decryption cannot be done on the server. More about AES-GCM.

Based on OWASP and NIST recommendations.

Practical Implementation of Encryption in Laravel

Laravel encryption tools provide transparent data protection. We use custom casts to encrypt sensitive fields automatically.

// app/Casts/EncryptedCast.php

class EncryptedCast implements CastsAttributes
{
    public function get($model, string $key, $value, array $attributes): ?string
    {
        if (is_null($value)) return null;
        try {
            return Crypt::decryptString($value);
        } catch (DecryptException) {
            return null;
        }
    }

    public function set($model, string $key, $value, array $attributes): ?string
    {
        if (is_null($value)) return null;
        return Crypt::encryptString($value);
    }
}

// In the model
class Patient extends Model
{
    protected $casts = [
        'passport_number' => EncryptedCast::class,
        'medical_notes'   => EncryptedCast::class,
        'snils'           => EncryptedCast::class,
    ];
}

// Usage — transparent to the code
$patient->passport_number = '4510 123456'; // automatically encrypted
$decrypted = $patient->passport_number;     // automatically decrypted

Advantages of Envelope Encryption

Storing encryption keys in the database alongside encrypted data is pointless. The best practice is envelope encryption: data is encrypted with a Data Encryption Key (DEK), the DEK is encrypted with a Key Encryption Key (KEK), and the KEK is stored in KMS/Vault. This allows re-encrypting data without access to the KEK and simplifies rotation.

HashiCorp Vault integration:

$vault = new Vault([
    'address' => 'https://vault.internal:8200',
    'token'   => env('VAULT_TOKEN'),
]);
$keyData = $vault->read('secret/data/app-encryption-key');
$encryptionKey = $keyData['data']['key'];

AWS KMS:

use Aws\Kms\KmsClient;
$kms = new KmsClient(['region' => 'eu-west-1']);
$result = $kms->encrypt([
    'KeyId'     => 'arn:aws:kms:eu-west-1:123456:key/abc-123',
    'Plaintext' => $sensitiveData,
]);
$encryptedData = base64_encode($result['CiphertextBlob']);

Searching Over Encrypted Data

Standard AES-GCM produces different ciphertext for the same value. Searching an encrypted field is impossible. Solutions:

Option 1: Hash for search + encryption for storage:

class PersonalDataRepository
{
    public function findByPassport(string $passport): ?Patient
    {
        $hash = hash_hmac('sha256', $passport, config('app.search_key'));
        return Patient::where('passport_hash', $hash)->first();
    }

    public function store(string $passport): void
    {
        Patient::create([
            'passport_data' => Crypt::encryptString($passport),
            'passport_hash' => hash_hmac('sha256', $passport, config('app.search_key')),
        ]);
    }
}

Option 2: PostgreSQL pgcrypto:

INSERT INTO patients (passport)
VALUES (pgp_sym_encrypt('4510 123456', current_setting('app.encryption_key')));

SELECT pgp_sym_decrypt(passport::bytea, current_setting('app.encryption_key'))
FROM patients WHERE id = 1;

Comparison of Data Protection Methods

Case Study: Encryption in a Medical CRM (From Our Practice)

Client — a network of clinics with 50,000 patients. Requirement: encrypt passport data, SNILS, diagnoses. We chose AES-256-GCM + envelope encryption with HashiCorp Vault. Implemented Laravel Casts for transparent encryption. Added HMAC hash for searching by policy number. Result: response time unchanged, security audit passed, 152-FZ compliance certificate obtained. The solution scales to any number of records.

What's Included in the Work

• Designing the encryption architecture considering business logic
• Selecting algorithms and key management scheme (envelope encryption)
• Integration with HashiCorp Vault or AWS KMS
• Implementing transparent encryption at the ORM level (Laravel, Doctrine, etc.)
• Configuring deterministic encryption for search
• Key rotation with zero downtime
• Access auditing and operation logging
• Documentation for the team and developer training
• Transferring access and test scenarios

Pricing: from $3,000 for small projects, $10,000+ for enterprise with custom integration.

Implementation Process and Timeline

1. Designing encryption schema and key management (1-2 days).
2. Implementing encryption at the model level (2-3 days).
3. Integration with external key stores (5-7 days).
4. Deterministic encryption for search (+3 days).
5. Implementing key rotation with zero downtime (+2 days).
6. Access auditing and operation logging (+1-2 days).
7. Documentation and team training (+1 day).

Final timeline — from 2 weeks to 2 months, depending on data volume and business logic complexity. This investment typically pays for itself by avoiding just one major data breach fine – savings of up to $500,000 under 152-FZ or millions under GDPR.

We offer turnkey implementation starting from $3,000. Contact us for a free evaluation of your project.

Web Application Security: HTTPS, CSP, XSS, CSRF, WAF, DDoS Protection

A website breach rarely looks like in movies. More often it's: a bot finds an unprotected /admin/export endpoint, downloads the customer database, and closes the connection. Or: through an outdated WordPress plugin, a web shell is uploaded, and the server starts sending spam. Or quieter: an XSS in a comment field allows stealing admin session cookies, unnoticed for months. We have analyzed dozens of such cases — each vulnerability could have been fixed at the development or audit stage.

Web application security is not a single setting. It's layers of protection, each closing a separate class of attacks. Order an audit — we'll assess the project and deliver a turnkey plan within 2–4 weeks.

How do we ensure comprehensive web application security?

HTTPS and Proper TLS Configuration

HTTPS is the minimum mandatory level. But having an SSL certificate and having a properly configured TLS are different things.

In Nginx/Apache configuration we check:

• Protocols: only TLS 1.2 and TLS 1.3, SSLv3 and TLS 1.0/1.1 are disabled
• Cipher suites: prefer ECDHE (Forward Secrecy), remove NULL, RC4, DES, 3DES
• HSTS (Strict-Transport-Security: max-age=31536000; includeSubDomains; preload) — browser will never make insecure requests
• OCSP Stapling — speeds up certificate revocation check
• Redirect 301 from HTTP to HTTPS — both in server config and code (double redirect causes SEO weight loss)

Check: SSL Labs (ssllabs.com/ssltest) should show A or A+. If B, the configuration is weak.

Let's Encrypt + Certbot for production is standard. Automatic renewal via certbot renew in cron. Wildcard certificates for subdomains via DNS-01 challenge.

Content Security Policy: The Most Powerful and Complex Protection

CSP is an HTTP header that tells the browser which sources are allowed to load resources. A properly configured CSP completely blocks most XSS attacks, even if the vulnerability exists in the code.

The problem: breaking the site with an incorrect CSP is easy. default-src 'none' — and fonts, images, JS stop working. So we start with Content-Security-Policy-Report-Only — CSP logs violations but does not block anything. We monitor reports for 2–4 weeks, refine the policy, then switch to enforcement mode.

Example of a real policy for a site with Google Analytics, Google Fonts, and Stripe:

Content-Security-Policy:
  default-src 'self';
  script-src 'self' https://www.googletagmanager.com https://js.stripe.com 'nonce-{random}';
  style-src 'self' https://fonts.googleapis.com 'unsafe-inline';
  font-src 'self' https://fonts.gstatic.com;
  frame-src https://js.stripe.com;
  img-src 'self' data: https://www.google-analytics.com;
  connect-src 'self' https://api.stripe.com https://www.google-analytics.com;
  report-uri /csp-report;

nonce — a random string generated server-side per request. Inline scripts with the correct nonce are allowed; without nonce, they are blocked. This completely breaks XSS via <script>alert(1)</script>.

'unsafe-inline' in style-src is a compromise for inline styles. It's better to remove it by moving all styles to CSS files, but that requires refactoring.

Why XSS Remains the Most Common Vulnerability?

XSS (Cross-Site Scripting) — injection of JS code through user input. According to OWASP, XSS is in the top 3 web application vulnerabilities. Three types:

Protection: never insert user input into HTML without escaping. In PHP — htmlspecialchars() with ENT_QUOTES. In Laravel Blade templates — {{ $var }} is safe, {!! $var !!} is dangerous. In React — {variable} is safe, dangerouslySetInnerHTML is dangerous. For Rich Text — use htmlpurifier on PHP or DOMPurify in the browser.

CSRF: Protecting Forms and APIs

CSRF (Cross-Site Request Forgery) — an attacker forces the victim's browser to send a request on their behalf. Example: a user is logged into a bank, opens a malicious page, which makes fetch('https://bank.ru/transfer?to=evil&amount=50000') — if the bank is unprotected, money is transferred.

CSRF tokens — standard protection for forms: the server generates a random token, stores it in the session, and inserts it as a hidden field in the form. On POST request, the token is verified. The attacker does not know the token. Laravel does this automatically with @csrf.

SameSite cookies — modern protection: SameSite=Strict or SameSite=Lax prevents the browser from sending cookies in cross-site requests. Works in all modern browsers.

API without sessions (JWT, Bearer tokens) — CSRF is irrelevant if the token is not stored in a cookie (but in the Authorization header or localStorage). However, localStorage is vulnerable to XSS — so for sensitive data, HttpOnly cookies with SameSite are preferable.

WAF and DDoS Protection

WAF (Web Application Firewall) filters HTTP traffic for attacks: SQL injection, XSS, path traversal, known exploit patterns. Options:

• Cloudflare WAF — cloud-based, OWASP Top 10 rules out of the box, custom rules via expressions. Managed Rules automatically block new threats.
• ModSecurity (Nginx/Apache) — self-hosted, OWASP Core Rule Set (CRS). Flexible but requires tuning and monitoring of false positives.
• AWS WAF — for infrastructure on AWS, integrates with CloudFront and ALB.

DDoS protection. Cloudflare at L3/L4/L7 is the de facto standard for most sites. Automatic mitigation of volumetric attacks, Under Attack Mode during active attacks. For critical infrastructure — Cloudflare Magic Transit or specialized solutions (Qrator, StormWall for the Russian market).

Rate Limiting at the application level — an additional layer. Laravel ThrottleRequests middleware: 60 requests per minute per IP for general endpoints, 5 for /login and /password/reset. Redis as a counter store — mandatory for horizontally scalable systems (otherwise limits are not synchronized between servers).

Other Mandatory Measures

Security headers. Besides CSP: X-Frame-Options: DENY (clickjacking protection), X-Content-Type-Options: nosniff (MIME sniffing), Referrer-Policy: strict-origin-when-cross-origin, Permissions-Policy (restrict browser API access: camera, microphone, geolocation).

SQL injection. Prepared statements everywhere. No concatenation of user input into SQL strings. ORM (Eloquent, Doctrine) protects by default. $wpdb->prepare() in WordPress is mandatory.

Dependency updates. composer audit and npm audit in CI/CD pipeline. Dependabot or Renovate for automatic PRs with updates. Critical CVEs — patch within 24 hours.

Secrets and configuration. .env — never in Git. Secrets in production — via CI/CD environment variables (GitHub Secrets, GitLab CI Variables) or HashiCorp Vault. Leak detection: git-secrets, truffleHog in pre-commit hooks.

How We Work

1. Audit — code scanning, configuration review, dependency analysis, manual business logic verification.
2. Planning — vulnerability remediation plan, stack selection (CSP, WAF, rate limiting).
3. Implementation — TLS setup, CSP configuration, headers, Rate Limiting, WAF.
4. Testing — re-penetration test, load testing, false positive check.
5. Deployment and Monitoring — enable production CSP, set up alerts, train the team.

What's Included

• Report with found vulnerabilities and recommendations (PDF + code snippets)
• Ready TLS configuration (Nginx/Apache)
• CSP policy with Report-Only and production versions
• WAF and Rate Limiting setup
• Dependency update plan
• Access to monitoring tools (Sentry, Datadog)
• 30 days of post-audit support (consultations, fixes)

Timeline and Cost

The budget is calculated individually — contact us for a project evaluation.