Comment by tristor | Hacker News Reader

Comment by tristor | Hacker News Reader

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I'm surprised by so many of the comments here out-of-hand dismissing or denigrating any password manager that stores data in the cloud. There are ways to store data securely, one of the simplest methods is to do zero-knowledge encryption of that data by way of key-generation from a password only the user knows at the time of decryption. This is essentially how the vault functionality of most password managers work, whether that vault is stored locally or not. They used something like PBKDF2 to generate the key used for encryption from your password.

There's no such thing as perfect security, but as a security-minded person I see nothing there to concern me simply because the data is stored in a company's S3 environment vs on Dropbox vs on my local disk. Presuming that the software itself has not been maliciously modified to leak the key, then regardless of where the data is stored it either requires breaking the encryption or finding the password that generated the key in order to access the data. My local disk is no more secure in that aspect, except that I may have the illusion of control. Availability is also an aspect of data security (in the CIA triangle) and a cloud provider that properly replicates and manages backups of data is more reliable than my local disk in this aspect and a fair trade-off for data I likely want to synchronize across systems and devices (phone and laptop, at minimum).

Why should you trust a password manager?

For me, it's pretty simple. I don't use social login, and I use unique usernames (most of the time) and passwords (every time) for hundreds of sites I've created accounts on over the years. This is because breaches /will/ happen, and password re-use is probably the single largest issue for user security, including for "power users" like myself. A password manager of /some kind/ is basically required to have unique passwords across hundreds to thousands of sites. Certainly, there's more to it, and you need to figure out your own threat model and trust constraints, and I can't solve that for you. But as far as I am concerned, if I have a reasonable assurance that the right algorithms are used and those algorithms are correctly implemented by the password manager software, I see no reason to distrust it.

> There are ways to store data securely, one of the simplest methods is to do zero-knowledge encryption of that data by way of key-generation from a password only the user knows at the time of decryption.

This keeps your passwords save until you enter your master password. At that point you have to trust the software that was downloaded a few days ago from an appstore or a few seconds ago from the company webserver. It might have been backdoored and happily phone home your master password.

Your downloaded password manager might be a few years old and YOU decide when to upgrade.

Your argument has nothing to do with cloud storage or password managers generally and seems to be an argument against automatic updates. So, fine, disable automatic updates (although I'd argue you're safer with them).

I also baked in the presumption that the software isn't malicious in my comment and called it out. So, sure, yes malware that leaks your password can exist. That doesn't really have any effect on whether password managers are a good thing or trustworthy.

I use 1password7 in a mode where I have to manually sync my vault. I've used other tools to prevent 1password from initiating any network connectivity at all.

And what threat model does this satisfy?

If the client for a cloud password manager is open-source, I'm inclined to trust it about as much as I would a non-cloud open-source password manager.

Ultimately I just wouldn’t use a password manager if it wasn’t synced with the cloud and didn’t offer simple browser integration. Sure, that increases the attack surface. But the alternative is not that I put loads more effort into faffy open source workflows, it’s that I go back to using crap passwords.

The safety of ciphertext stored in the cloud is entirely dependent on the lack of state level actors interfering in encryption research, cipher engine design, chip manufacture, operation of cloud hardware, and day to day safety of cloud operator employees.

The USA has been shown to be quite willing to violate all those conditions: NSA directly influencing cipher design, interfering with chip manufacture, seizing hardware wholesale, and engaging in “enhanced interrogations” in attempts to extract information.

The threat level of this state action is 100% because they aren’t going o spend all that time and money on these tools and not use them. They aren’t focussed on cracking your password, they just crack everyone’s because that is easier to automate (see prior discussion regarding weakening encryption to suit the tools the TLAs already have access to).

At least with my secrets stored on my hardware I have the assurance that the TLAs will need to be targeting me directly in order to obtain my secrets (much less likely than getting caught up in a dragnet).

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