Comment by forgotpw2726 | Hacker News Reader

Comment by forgotpw2726 | Hacker News Reader

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I've been thinking about something similar, it really should be much easier to send encrypted messages.

I'm not sure if this is a problem, but one thing that is unclear to me is how/if this protects against an adversary that can modify the html file.

If the adversary can modify the HTML file in transit they can just add some code that sends the password to the adversary's server when the real recipient opens the file. (Of course, the recipient can run it in some air gapped browser etc, but that limits the practical use case quite a lot.)

And if you want to use this to send messages over e.g. email this seems like a somewhat important thing to protect against. I guess you could send the portable secret html file separately, and then the user copy-pastes the message in some text-box, but again this makes it more clunky.

Phishing is indeed the most glaring vulnerability of this.

While it's very real in theory, I am not concerned in practice.

If I am the target of a sophisticated attacker, there are easier and more effective ways to pwn me.

A few other comments reference the same, e.g.: https://news.ycombinator.com/item?id=34085245

Fair enough, I guess in many ways I agree that at least for now it is not a real world problem. But if this would become popular it wouldn't be that hard to make a proxy that silently adds some code to the page if you fetch it over the internet.

Maybe it would be good to document this a bit more clearly that this mainly protects against weak adversaries. On the website you make some comparisons to GPG etc, which is a very different level of protection from my understanding, and may give a false sense of security.

I think I would prefer an approach where each person has their own html file, and then they can copy-paste the message into a text box and then decrypt it. Then you could also use public-key cryptography etc, and store a (encrypted) private-key in the html file itself. Like a light-weight GPG client in a single static html page. I guess the main feature that I don't see how to add is how to store and keep track of the public keys for your friends in a nice way.

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