Web Security Guides
11 articlesWeb security is the foundation of every trustworthy application. A single vulnerability — an unescaped input, a misconfigured header, or a leaked API key — can expose user data, destroy brand reputation, and trigger costly regulatory penalties under GDPR, CCPA, and PCI-DSS. These guides cover the full spectrum of modern web security: from preventing cross-site scripting (XSS) and cross-site request forgery (CSRF) at the application layer, to implementing HTTP security headers (Content-Security-Policy, HSTS, X-Frame-Options) at the infrastructure layer. You will learn how to think like an attacker — understanding threat models, attack surfaces, and the OWASP Top 10 — so you can build defenses that actually work. Each article includes practical code examples, real-world vulnerability case studies, and step-by-step remediation guides that you can apply immediately to your projects.
What You'll Learn
- How to prevent XSS, CSRF, SQL injection, and other OWASP Top 10 vulnerabilities
- Implementing Content-Security-Policy, HSTS, and other HTTP security headers correctly
- Password hashing best practices: bcrypt, scrypt, Argon2 — and why SHA-256 is wrong for passwords
- Secure authentication flows: JWT handling, session management, and OAuth 2.0 pitfalls
- HTML entity encoding, input sanitization, and context-aware output escaping
- SSL/TLS certificate management and HTTPS configuration for production deployments
Why This Matters
The average cost of a data breach reached $4.45 million in 2023 (IBM Security). Most breaches exploit known vulnerabilities that proper security practices would have prevented. These guides give you the knowledge to build secure-by-default applications, pass security audits, and protect your users — without needing a dedicated security team.
All Articles
JWT Security: What's Safe to Decode, and What You Should Never Paste Online
A JWT is just Base64 — anyone can read it. What that means for inspecting tokens safely, why pasting a live token into a random website is risky, how signature verification actually protects you, and what belongs in a token.
Are Online PDF Tools Safe? Server Upload vs In-Browser Editing
What actually happens when you upload a PDF to an online tool — server retention, breach exposure, and jurisdiction — and how in-browser PDF editing avoids it. With a practical way to verify any tool yourself.
HTTP Security Headers: The Complete Checklist for Your Web App
A definitive engineering guide to HTTP Security Headers. Master Content-Security-Policy (CSP), Strict-Transport-Security (HSTS), X-Frame-Options, and defend against XSS, clickjacking, and MIME sniffing attacks.
SSL/TLS Certificates: What Developers Should Know
A practical guide to SSL/TLS certificates: the TLS handshake, the chain of trust, ACME/Let's Encrypt automation, debugging missing intermediates, and hardening Nginx.
CORS Errors Explained: Why Your Fetch Call Fails and How to Fix It
A practical guide to CORS: the Same-Origin Policy, debugging OPTIONS preflight requests, the wildcard-plus-credentials paradox, and securing it with an Nginx reverse proxy.
Password Security: Generation, Hashing, and Storage Best Practices
A guide to password security: information entropy, bcrypt vs Argon2id hashing, salting to defeat rainbow tables, and the current NIST guidelines.
API Rate Limiting: How It Works and How to Handle It
A practical guide to API rate limiting: how token buckets and sliding windows work, implementing them in Redis with atomic Lua scripts, and writing client retry logic with exponential backoff and jitter.
bcrypt vs SHA-256: Password Hashing Compared
Why SHA-256 is wrong for password storage and bcrypt is right. Learn about salting, key stretching, and modern password hashing best practices with real benchmarks and implementation examples.
XSS Prevention with HTML Entity Encoding
The definitive engineering guide to Cross-Site Scripting (XSS). Master Context-Aware HTML Entity Encoding, Content Security Policy (CSP) nonces, DOM-based attacks, and the Trusted Types API to eradicate injection vulnerabilities.
Why Base64 is Not Encryption
Why Base64 encoding provides no security: how the algorithm works, the real Kubernetes/JWT misconceptions, and how to use AES-256-GCM and bcrypt instead.
Web Security: Encoding and Hashing Guide
Understand the differences between encoding, hashing, and encryption. Learn when to use Base64, SHA-256, bcrypt, AES, and HTML entity encoding for web security — with code examples and decision flowcharts.