How to Secure Your Angular Project from the Polyfill.io Security Threat

To address the security alert regarding Polyfill.io for Google Maps Platform users in Angular, here’s a step-by-step approach to mitigate the issue:

Background

Polyfill.io has been compromised following its acquisition by a Chinese company, resulting in a supply chain attack that injects malicious code into websites using the service. This malicious code can redirect users to unwanted sites and potentially cause further security risks.

Steps to Mitigate the Issue

1. Remove Polyfill.io Scripts:
   • Identify and remove any references to cdn.polyfill.io in your Angular project. This includes scripts in your HTML files and any configurations that load these scripts dynamically.
2. Use Trusted Alternatives:
   • Replace Polyfill.io with a trusted source. Cloudflare provides a safe mirror for Polyfill.io, which can be used as a direct replacement. For example:
     <script src=”https://cdnjs.cloudflare.com/ajax/libs/polyfill/7.11.0/polyfill.min.js”></script>
3. Implement Subresource Integrity (SRI):
   Ensure the integrity of the scripts you load by using SRI. This involves adding a hash to your script tags to verify that the content has not been tampered with.
   <script src=”https://cdnjs.cloudflare.com/ajax/libs/polyfill/7.11.0/polyfill.min.js” integrity=”sha384-xyz” crossorigin=”anonymous”></script>
4. Regular Security Audits:
   Conduct regular security audits of your project to identify and mitigate any vulnerabilities. Utilize security tools and services to scan for potential threats.
5. Stay Updated:
   Keep informed about the latest security updates and best practices by following reputable sources and subscribing to security alerts.

Example in Angular

Here’s how you might update your Angular project to replace Polyfill.io:

Before:

<!– index.html –> <script src=”https://cdn.polyfill.io/v3/polyfill.min.js?features=default”></script>

After:

<!– index.html –> <script src=”https://cdnjs.cloudflare.com/ajax/libs/polyfill/7.11.0/polyfill.min.js” integrity=”sha384-xyz” crossorigin=”anonymous”></script>

Resources

• Cloudflare Blog on Polyfill.io Issue
• SecurityWeek Article on Polyfill.io Attack
• BleepingComputer Article on Polyfill.io Security Issue

By following these steps, you can mitigate the risks associated with the Polyfill.io compromise and ensure your Angular project remains secure.