Emergency Access: How We Share Your Encryption Keys Without Ever Seeing Them

You've encrypted your most important files with client-side encryption. Your vault is secure - even we can't read it. But there's a problem: what happens when your family needs access and you're not there to help?

Today, we're introducing Emergency Access - a feature that lets you share your vault's encryption key with trusted people, without us ever seeing it. This might sound impossible, so let's break down exactly how it works.

The Problem: Encryption is a Double-Edged Sword

Client-side encryption means your files are encrypted on your device before they're uploaded to our servers. We never see your encryption key - that's the whole point.

This is great for privacy: your files are truly private, we can't be compelled to hand them over, and even if we were hacked, attackers couldn't read your data.

But it creates a problem: if you're incapacitated, no one else can access your vault. Your family can't just "reset your password" - the encryption that protects you also locks them out.

We needed a way to share your encryption key with people you trust - but only when you want them to have it, and without us ever seeing it.

The Solution: Zero-Knowledge Key Sharing

Emergency Access uses a clever technique based on how URLs work. When you share a URL like https://example.com/page#secret, the part after the # (called the "fragment") is never sent to the server. This is a fundamental part of how the web works - browsers only use fragments locally.

We use this browser behavior to create a secure key-sharing system. Here's how it works:

1. You create a link. Your browser generates a random secret and encrypts your vault key with it.
2. The link is split in two. The encrypted vault key goes to our server. The secret that decrypts it goes in the URL fragment (after the #).
3. Someone uses the link. Their browser extracts the secret from the URL fragment - which never gets sent to our server.
4. Decryption happens locally. Their browser downloads the encrypted payload from our server, decrypts it using the secret from the URL, and reveals your vault key.

The result: we only ever see the encrypted payload, which is useless without the secret. The secret only exists in the URL you share - never on our servers.

Why This is Secure

This design has several important security properties:

• We never see your key. The link secret never leaves your browser. We only store the encrypted payload.
• It's based on web standards. URL fragments not being sent to servers isn't our feature - it's how the web has worked for decades.
• You stay in control. You must approve each access request. No one can use the link without your explicit permission.

What If Inheritfy Were Compromised?

Let's imagine the worst-case scenario: an attacker gains complete access to our servers. Here's what they would find:

The attacker would have encrypted blobs they cannot decrypt. Your vault key is safe because half of the puzzle (the link secret) only exists in the URLs you've shared - never on our servers.

How to Set It Up

Getting started with Emergency Access is simple:

1. Go to your vault settings. Open any vault and click on "Emergency Access" in the settings menu.
2. Create a link. Click "Create Emergency Access Link". Your browser will generate the secure link.
3. Share securely. Copy the link and share it with someone you trust. Use an encrypted messenger or share it in person - don't email it in plaintext.
4. Manage requests. When someone uses your link, you'll get a notification. Review and approve or deny from your dashboard.

The Bottom Line

Emergency Access solves one of the hardest problems in secure storage: giving others access to your encrypted data without compromising security. By splitting the secret between the URL fragment (which stays client-side) and our server (which stores the encrypted payload), we've created a system where:

• You maintain complete control over who can access your vault
• Your encryption key is never exposed to us or anyone without the link
• Someone with only the link can't access anything without your approval
• Even a complete breach of our servers wouldn't expose your key

This is the power of zero-knowledge architecture - enabling secure collaboration without sacrificing privacy.