Why Isn’t True Zero-Trust Encryption Used in Email Systems?

Mithun GS — Tue, 09 Dec 2025 08:07:18 +0000

Most “secure email” platforms still rely on provider-managed keys:
either the provider generates the user’s key pair, or stores an encrypted copy for sync, or encrypts stored mail with server-side keys. In all cases, the provider retains theoretical decrypting capability.

A strict zero-trust model would require:

user-generated private keys

provider never storing or handling private keys

stored mail encrypted only with the user’s public key

no server-side key material that could decrypt data

provider cryptographically incapable of accessing message content

This model is common in password managers and zero-knowledge file storage, but rarely seen in email.

So the question is:

What stops email providers from adopting true zero-trust storage?

Is it:

key-management friction for users?

multi-device sync challenges?

server-side search/indexing requirements?

business reasons?

or just legacy expectations around email UX?

Curious how others in the dev/crypto community see this.

I Checked Proton Mail’s Security… and I Was Not Ready for What I Saw 😳

Mithun GS — Mon, 08 Dec 2025 07:21:39 +0000

I’m building Millionaire.email, a security-first email service.
And like everyone else, I’ve always heard:

“Proton Mail is the most secure email on the planet.”

So I got curious.
How did Proton get so much hype?
Let me check their security… should take 5 minutes, right?

Yeah. NO.
That was the last peaceful thought I had. 😂

I started checking DNSSEC… DANE… MTA-STS… TLS-RPT… DKIM…
One by one…

And instead of finishing in minutes, I ended up sitting there like:

“Wait… this can’t be right… WHAT?!” 😳

DNSSEC not fully enforced

No ED25519 DKIM

No DANE/TLSA

MTA-STS gaps

TLS-RPT missing in places

I genuinely thought Proton would be flawless.
But I got plot-twisted by reality.

If you want the full technical breakdown (with proof):
👉 https://www.millionaire.email/post/millionaire-email-vs-proton-me-complete-security-architecture-comparison-2025

Not throwing hate — Proton is good.
But as someone building a secure email from scratch, this was a shock + comedy + motivation moment.

And it made my philosophy even stronger:

Don’t trust us. Verify us. 🔐

Forem: Mithun GS

Why Isn’t True Zero-Trust Encryption Used in Email Systems?

I Checked Proton Mail’s Security… and I Was Not Ready for What I Saw 😳