Everything You Need To Know About Let's Encrypt And Chain Of Trust

If you are an online business owner or a blogger, you have probably heard about Let’s Encrypt and the chain of trust. These are the common security terms you will hear when you start a blog.

But how does it impact your business?

Do you need to change your SSL certificate configuration to ensure 100% compatibility?

That’s what we will talk about in this blog post.

Here, we will show you everything you need to know about Let’s Encrypt and chain of trust.

Let’s Encrypt: An Introduction

Let’s Encrypt And Chain Of Trust

Let’s Encrypt is at the forefront of internet security, offering a revolutionary SSL/TLS certificate issuance approach. Launched with the vision of a safer web, it is a free, automated, and open certificate authority provided by the Internet Security Research Group (ISRG).

It was created to simplify securing websites with HTTPS, enhancing privacy and security for internet users worldwide. Let’s Encrypt’s mission is to encourage the universal adoption of HTTPS. Making encrypted web connections the norm rather than the exception.

By providing certificates at no cost, Let’s Encrypt eliminates one of the major barriers to web encryption. The expense and complexity traditionally associated with obtaining SSL/TLS certificates. What makes Let’s Encrypt particularly groundbreaking is its commitment to automation.

The ACME protocol allows for the automated issuance and renewal of certificates, meaning website administrators can set up encryption without extensive technical knowledge or manual intervention. This automation simplifies the process and helps maintain security by ensuring certificates are always up to date.

What Is Chain of Trust

The chain of trust is a fundamental concept in cybersecurity, particularly within the public key infrastructure (PKI) framework. It refers to the sequence of certificates that certify each other’s authenticity, starting from a trusted root certificate through various intermediate certificates down to the end-entity or leaf certificate installed on a server.

This chain ensures that each link is validated by the one before it, creating a verifiable path of trust back to a known and trusted root CA. The root certificate is at the heart of this system. Software like web browsers and operating systems inherently trust it because it’s issued by a Certificate Authority (CA) that has been vetted and included in their trust stores.

Intermediate certificates are issued from this root, which can issue further certificates. Each certificate in this chain contains cryptographic keys used to sign and verify the integrity and authenticity.

The chain of trust is crucial during secure communications, such as when a user’s browser connects to a website over HTTPS.

Here, the server presents its SSL/TLS certificate. And the browser checks its authenticity by tracing it back through the chain of trust. The browser will alert the user if a certificate is untrusted, expired, or broken, indicating potential security risks.

Let’s Encrypt And Chain Of Trust: What Will Happen

Multiple things will happen with Let’s Encrypt and Chain of Trust. The major changes are going to be:

  • Transition to Shorter Chain
  • End of Cross-Signing
  • ECDSA Certificates
  • Impact on Older Devices
  • Security and Performance

Below, we will examine each of the modifications in more detail and consider how they will impact the current situation.

Transition to Shorter Chain

Starting from June 6, 2024, Let’s Encrypt has begun issuing certificates with a shorter chain of trust. This means the default certificate chain provided during TLS handshakes will directly link to ISRG Root X1 without the intermediate step involving the cross-sign from the older root, DST Root CA X3.

This change aims to simplify the trust model, enhance security, and improve performance by reducing the certificate chain length.

End of Cross-Signing

The cross-signing by DST Root CA X3, which was used to ensure compatibility with older systems, particularly older Android versions, has been phased out. This means that systems or devices that only trusted the older root might have issues unless they’ve updated to recognize ISRG Root X1 or newer chains.

ECDSA Certificates

Let’s Encrypt has started to issue ECDSA (Elliptic Curve Digital Signature Algorithm) certificates from ECDSA intermediates. This move modernizes their offerings and aims to provide better security with more efficient cryptographic operations.

Websites will now receive an ECDSA certificate that traces back through a single ECDSA intermediate to ISRG Root X1 or potentially to ISRG Root X2 as an alternate chain.

Impact on Older Devices

Devices running outdated versions of Android or other old systems might face trust issues with websites using new Let’s Encrypt certificates.

If these devices haven’t updated their trust stores, they will not recognize the newer chains without the cross-sign. However, with the widespread adoption and updates in mobile operating systems, this impact is expected to be minimal and diminishing over time.

Security and Performance

The shorter chain reduces the complexity of certificate validation, potentially leading to slightly faster TLS handshakes. From a security perspective, this transition reduces reliance on an older root certificate, aligning with current cryptographic standards.

Impact on End Users

From a user experience perspective, there’s no noticeable change if everything works as intended. Websites load securely with browsers’ typical HTTPS indicators (like a lock icon). However, for those affected by compatibility issues, their experience might be disrupted, prompting software updates or, worst cases, device upgrades.

For most users, this transition means slightly improved security and potentially faster TLS handshakes due to the shorter chain of trust. This improvement directly benefits end users by reducing the time it takes to establish a secure connection, enhancing their browsing experience through quicker page loads, and reinforcing security.

This change might highlight digital divide issues for users in regions with limited access to new technology. While not directly responsible, Let’s Encrypt’s move might indirectly push for better global digital inclusivity by making the need for up-to-date technology more apparent.

Conclusion

Let’s Encrypt’s recent updates to its chain of trust, particularly the move towards a shorter chain linked directly to ISRG Root X1 and the introduction of ECDSA certificates. It reflects a nuanced balance between maintaining broad compatibility and advancing security standards.

By reducing the complexity of the certificate chain, Let’s Encrypt not only bolsters security through fewer points of potential failure but also enhances efficiency with quicker TLS handshakes.

This evolution in Let’s Encrypt’s approach reminds us of the ever-changing nature of cybersecurity. It calls for continuous education among developers, website owners, and end-users about staying current with security protocols and system updates.

Do you need to make any modifications to your SSL configuration?

Let us know in the comments.

Sreehari P Raju
Sreehari P Raju

Sreehari P Raju is a freelance WordPress content writer. He started using WordPress in 2015 and loves writing tutorials, product reviews, and listicles. While not working, he loves playing Minecraft or eating KFC.

Related Posts