Are you building your web applications with security in mind? I know that with all the things developers have to juggle, it’s easy to overlook security features. For one, web security is a whole different field in its own right. It can feel very overwhelming when first getting into it. Even just knowing where to start feels hard. After working on a very security-focused project for a while now, I’ve learned quite a bit and am happy to share some security tips I’ve learned. I figured it would be really nice to lay out a few quick and effective security practices I highly recommend adding to your workflow.
1. Lock down your content with a content security policy (CSP).
A Content Security Policy (CSP) is an easy way to help prevent cross-site scripting (XSS) and other code injection attacks. It works by telling the browser which sources are allowed to load content like scripts and styles, blocking anything else that could be a potential security risk.
Here’s a basic CSP header you can add to your web app:
Content-Security-Policy: default-src ‘self’; script-src ‘self’ https://trusted-site.com; style-src ‘self’ ‘unsafe-inline’
This makes sure scripts and styles can only be loaded from your own domain or a trusted source. If something isn’t explicitly allowed, it won’t run—keeping your app safer. Make it a habit to review and update your CSP regularly.
2. Sanitize any HTML before saving it to your database.
If users can submit content (comments, notes, posts, etc.), be sure to sanitize the HTML before saving it. If you don’t, you leave the door open for stored XSS attacks, where malicious scripts are injected into your pages and run when other users visit them.
Use a library designed for this, like sanitize-html for javascript. These will strip out any potentially harmful code while keeping the good stuff.
For example, here’s how you can use sanitize-html:
import sanitizeHtml from "sanitize-html";
const cleanHTML = sanitizeHtml(userInput);
database.save(cleanHTML);
Sanitizing before saving means attackers can’t sneak in harmful scripts that execute later, keeping your users and your site safe.
3. Use only trusted third-party services and configure them securely.
Third-party services can save a ton of time, but if you’re not careful, they can also introduce security risks. Always vet your third-party providers before integrating them into your app.
- Check for security certifications like SOC 2, ISO 27001, or compliance with regulations like GDPR or HIPAA.
- Read their security docs to make sure you’re using their service safely.
- Restrict API keys and permissions so they only have the access they truly need.
- Keep an eye on security updates and update your integrations regularly.
For example, if you’re using an authentication service like Auth0, make sure you’re securing webhooks properly, limiting API keys, and enabling multi-factor authentication (MFA) for your account.
Final Thoughts
Security doesn’t have to be overwhelming. By setting up a Content Security Policy (CSP), sanitizing HTML before saving it, and being mindful of third-party services, you’ll be in a much better place security-wise. Give these tips a try and let me know if they help. You might even start to enjoy thinking about security rather than seeing it as an afterthought!