- by x32x01 ||
HTML5 introduced many powerful features for developers - but with great power comes great responsibility 
. To keep your web apps safe from modern threats, you need to apply smart security practices. Let’s explore the most important ones 
Content Security Policy (CSP)
CSP helps block Cross-Site Scripting (XSS) attacks by controlling which resources (scripts, images, styles) can be loaded on your page.
Example:
This ensures only trusted scripts can run on your site.
Cross-Origin Resource Sharing (CORS)
CORS defines which external domains can access your resources. Without it, attackers could trick your browser into sending unauthorized requests.
Tip: Always specify trusted origins only - never use
Secure Input Handling
Validate and sanitize all user input before processing it. This prevents SQL injection, XSS, and form-based attacks.
Best practice:
Same-Origin Policy (SOP)
SOP prevents malicious scripts from interacting with content from other sites. It’s the cornerstone of browser security - don’t disable it unless absolutely necessary.
Web Storage & Cookies
Sensitive data should never be stored in plain text.
HTTPS Everywhere
Always use HTTPS to encrypt communication between the client and the server. This stops man-in-the-middle attacks and keeps data private.
Subresource Integrity (SRI)
SRI checks that external files (like scripts or styles from CDNs) haven’t been tampered with.
Example:
Final Tip
Following these principles will make your HTML5-based web applications much safer from common attacks. For a deeper dive into browser security and real-world examples, visit 
html5sec.org
Stay safe, code smart, and never trust unchecked input
. To keep your web apps safe from modern threats, you need to apply smart security practices. Let’s explore the most important ones Content Security Policy (CSP) 
CSP helps block Cross-Site Scripting (XSS) attacks by controlling which resources (scripts, images, styles) can be loaded on your page.Example:
HTML:
<meta http-equiv="Content-Security-Policy" content="default-src 'self'; script-src 'self' https://apis.google.com;">Cross-Origin Resource Sharing (CORS) 
CORS defines which external domains can access your resources. Without it, attackers could trick your browser into sending unauthorized requests.Tip: Always specify trusted origins only - never use
Access-Control-Allow-Origin: * for sensitive APIs.Secure Input Handling 
Validate and sanitize all user input before processing it. This prevents SQL injection, XSS, and form-based attacks.Best practice:
- Use HTML5 input types (e.g.,
email,number). - Escape special characters server-side.
Same-Origin Policy (SOP) 
SOP prevents malicious scripts from interacting with content from other sites. It’s the cornerstone of browser security - don’t disable it unless absolutely necessary.Web Storage & Cookies 
Sensitive data should never be stored in plain text.- Use encryption for localStorage/sessionStorage.
- Mark cookies as HttpOnly and Secure to protect them from theft via JavaScript or HTTP sniffing.
HTTPS Everywhere 
Always use HTTPS to encrypt communication between the client and the server. This stops man-in-the-middle attacks and keeps data private.Subresource Integrity (SRI) 
SRI checks that external files (like scripts or styles from CDNs) haven’t been tampered with.Example:
HTML:
<script src="https://cdn.example.com/script.js"
integrity="sha384-xyz123"
crossorigin="anonymous"></script>Final Tip 
Following these principles will make your HTML5-based web applications much safer from common attacks. For a deeper dive into browser security and real-world examples, visit html5sec.orgStay safe, code smart, and never trust unchecked input
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