GDPR Cookie Consent Banner for Websites

Imagine opening a website where the Facebook Pixel fires before you even click 'Accept'. That's a direct violation of Article 7 GDPR—active consent is required. The result: fines up to 4% of turnover or €20 million. We solve this with a consent mechanism featuring auto-blocking, ensuring tracking scripts don't load without explicit consent. Over 5 years, we've implemented 50+ solutions—from simple banners to integrations with OneTrust and custom systems. One project: an e-commerce site with 100k monthly visitors had a hidden Hotjar script running without consent—after implementing a custom banner with auto-blocking, legal risks dropped by 90%. A proper consent mechanism helps avoid fines. Get a consultation on implementation.

Why Categorizing Cookies Matters

Under GDPR, cookies are divided into categories, and users must be able to choose per category, not just 'Accept All'. The European Court of Justice ruling C-252/21 confirmed that a single 'Accept All' checkbox is insufficient. Users must be able to consent only to necessary cookies, e.g., analytics, while rejecting marketing. We implement an interface with checkboxes for each category, storing choices in localStorage and on the server. Withdrawal should be as easy as consent—a 'Only Necessary' button on the first banner screen.

How Auto-Blocking Mode Works

Auto-blocking mode blocks tracking scripts from executing until consent is obtained. Without it, scripts may load before consent, violating GDPR. Implementation can use ready-made solutions (Cookiebot, OneTrust) or a custom loader. We prefer the latter for full control, offering 10x more flexibility than typical banners. For example, a custom loader allows fine-grained script blocking by category and dynamic resource loading. Contact us for a detailed architecture discussion.

Example of loading Google Analytics only after consent:

export function useAnalytics() {
  const { consent } = useContext(CookieConsentContext);

  useEffect(() => {
    if (consent.analytics && !window.gtag) {
      const script = document.createElement('script');
      script.src = `https://www.googletagmanager.com/gtag/js?id=${GA_ID}`;
      document.head.appendChild(script);

      window.dataLayer = window.dataLayer || [];
      window.gtag = function() { window.dataLayer.push(arguments); };
      window.gtag('js', new Date());
      window.gtag('config', GA_ID, { anonymize_ip: true });
    }
  }, [consent.analytics]);
}

How to Verify Your Banner Complies with GDPR

Key criteria: user must give active consent before scripts load, withdrawal must be as easy as consent, and all consent records must be stored. Use tools like Cookie Scanner or browser extensions. If scripts load before interaction—the banner is non-compliant. Our engineers offer a free audit of your site. Guaranteed compliance with our trusted solution.

Technical Implementation: From Context to Component

Here's a full example with context and banner component. Code can be adapted for Next.js, Vue, or vanilla JavaScript.

// CookieConsentContext.tsx
interface ConsentState {
  analytics: boolean;
  marketing: boolean;
  functional: boolean;
}

const CookieConsentContext = createContext<{
  consent: ConsentState;
  updateConsent: (updates: Partial<ConsentState>) => void;
  hasResponded: boolean;
}>({} as any);

export function CookieConsentProvider({ children }: { children: ReactNode }) {
  const [consent, setConsent] = useState<ConsentState>({
    analytics: false,
    marketing: false,
    functional: false,
  });
  const [hasResponded, setHasResponded] = useState(false);

  useEffect(() => {
    const stored = localStorage.getItem('cookie_consent');
    if (stored) {
      const data = JSON.parse(stored);
      setConsent(data.preferences);
      setHasResponded(true);
    }
  }, []);

  const updateConsent = (updates: Partial<ConsentState>) => {
    const newConsent = { ...consent, ...updates };
    const record = {
      preferences: newConsent,
      timestamp: new Date().toISOString(),
      version: '1.0',
    };
    localStorage.setItem('cookie_consent', JSON.stringify(record));
    setConsent(newConsent);
    setHasResponded(true);

    // Send record to server
    fetch('/api/consent', {
      method: 'POST',
      body: JSON.stringify(record),
    });
  };

  return (
    <CookieConsentContext.Provider value={{ consent, updateConsent, hasResponded }}>
      {children}
    </CookieConsentContext.Provider>
  );
}

// CookieBanner.tsx
export function CookieBanner() {
  const { hasResponded, updateConsent } = useContext(CookieConsentContext);
  const [showDetails, setShowDetails] = useState(false);
  const [selections, setSelections] = useState({
    analytics: false, marketing: false, functional: true,
  });

  if (hasResponded) return null;

  return (
    <div className="cookie-banner" role="dialog" aria-label="Cookie consent">
      <p>We use cookies to improve your experience on our site.</p>

      {showDetails && (
        <div className="cookie-categories">
          <label>
            <input type="checkbox" checked disabled />
            Necessary (always active)
          </label>
          <label>
            <input type="checkbox"
              checked={selections.analytics}
              onChange={e => setSelections(s => ({...s, analytics: e.target.checked}))}
            />
            Analytics
          </label>
          <label>
            <input type="checkbox"
              checked={selections.marketing}
              onChange={e => setSelections(s => ({...s, marketing: e.target.checked}))}
            />
            Marketing
          </label>
        </div>
      )}

      <div className="cookie-actions">
        <button onClick={() => updateConsent({ analytics: false, marketing: false })}>
          Only Necessary
        </button>
        <button onClick={() => setShowDetails(!showDetails)}>
          Customize
        </button>
        <button className="primary"
          onClick={() => updateConsent({ analytics: true, marketing: true, functional: true })}>
          Accept All
        </button>
        {showDetails && (
          <button onClick={() => updateConsent(selections)}>
            Save Preferences
          </button>
        )}
      </div>
    </div>
  );
}

Storing Consent Records for Compliance

For compliance, a log must be maintained. We use a separate table with user identification (IP + fingerprint) and full history. Each record includes timestamp, policy version, and preferences. This proves compliance during audits. Our certified storage ensures data integrity.

// migrations/create_consent_records_table.php
Schema::create('consent_records', function (Blueprint $table) {
    $table->id();
    $table->string('user_identifier'); // IP + fingerprint or user_id
    $table->json('preferences');
    $table->string('version');
    $table->ipAddress('ip_address');
    $table->timestamp('consented_at');
    $table->timestamp('withdrawn_at')->nullable();
});

Scope of Work: Stages and Deliverables

1. Audit of existing scripts and cookies on the site.
2. Architecture design of consent mechanism (server + client).
3. Development of custom banner or configuration of a ready-made one.
4. Implementation of auto-blocking for tracking scripts.
5. Integration with analytics and CRM.
6. Documentation and team training.
7. Post-release support for one month.

Deliverables:

• Architecture and configuration documentation
• Source code of component and integrations
• Instructions for updating the cookie policy
• Team training (1 hour webinar)
• Post-release support for 1 month

Comparison: Custom vs. Ready-Made Solution

Custom implementation gives full control over design, logic, and performance. For projects with unique requirements, we recommend custom: LCP increase can be up to 200ms lower, making it 2 times faster.

Assessing Your Current Situation

Perform a cookie audit using a 'Cookie Scanner' extension or browser console. If you find scripts loading without consent—it's time to change the approach. Get a consultation on integration—our engineers will analyze your site for free. Trust our 5+ years of experience and guaranteed compliance.

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.