Free course

Web Application Security Course

Protect browser-based applications from XSS, injection, CSRF, unsafe uploads, SSRF, broken access control, and insecure deployment.

5 modules · 25 lessons · No signup

Prerequisites: Security Fundamentals, HTML, JavaScript and HTTP

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What you'll learn

Threat-model, harden, test, and operate a small web application across its browser, server, storage, and deployment boundaries.

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Course contents

  1. Browser security boundaries

    Reason about origins, cookies, CORS, CSP, storage, and trust between sites.

    1. ✓ Understand the origin boundary
    2. ✓ Protect session cookies
    3. ✓ Configure CORS narrowly
    4. ✓ Add a Content Security Policy
    5. ✓ Check your understanding: browser security boundaries

  2. Injection and output

    Prevent XSS, SQL injection, command injection, and path traversal.

    1. ✓ Prevent cross-site scripting
    2. ✓ Use parameterized database queries
    3. ✓ Avoid command injection
    4. ✓ Keep file paths inside a root
    5. ✓ Check your understanding: injection and output

  3. Requests, files, and servers

    Protect state changes, framing, uploads, and server-side network requests.

    1. ✓ Prevent cross-site request forgery
    2. ✓ Stop clickjacking
    3. ✓ Handle file uploads
    4. ✓ Control server-side requests
    5. ✓ Check your understanding: requests, files, and servers

  4. Access and configuration

    Enforce access control and secure headers, errors, production settings, and admin paths.

    1. ✓ Enforce object authorization
    2. ✓ Set security headers
    3. ✓ Fail without leaking internals
    4. ✓ Protect administrative surfaces
    5. ✓ Check your understanding: access and configuration

  5. Test and operate

    Plan authorized tests, monitor abuse, review releases, and verify fixes.

    1. ✓ Build a security test plan
    2. ✓ Test only with permission
    3. ✓ Monitor web abuse
    4. ✓ Complete a web security review
    5. ✓ Check your understanding: test and operate