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this post was submitted on 28 Sep 2023
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Stored in memory is still stored. It's still unencrypted during data processing. Still bad practice and a security vulnerability at best. Email isn't E2E encrypted.
there is no possible way to handle sensitive data without storing it in memory at some point
it’s where you do all the salting, hashing, and encrypting
emailing out credentials like this after sign up is certainly not best practice, but probably not a huge deal for a video game forum of all things. if you are re-using passwords then you already have a way bigger problem.
Understatement of the year right here. Everyone in this thread is more interested in dunking on OP for the few wrong statements they make rather than focusing on the fact that a service is emailing their users their password (not an autogenerated "first time" one) in plaintext in an email.
Since we're nitpicking here - technically you can. They could run hashing client side first, and instead of sending the password in plain-text, you'd send a hashed version
but then you expose your salt to the public
No, the client side hashing doesn't substitutes anything server side, it just adds an extra step in the client
This opens up the possibility of replay attacks in the case of data breaches, though, and those are much more common than http mitm attacks (made even less likely with the proliferation of https).
I'm not entirely sure whether hashing twice (local and server) is wise, having not thought through that entire threat vector. Generally I try to offload auth as much as I can to some sort of oauth provider, and hopefully they'll all switch over to webauthn soon anyway.
I'm not really sure how it opens up replay attacks, since it doesn't really change anything to the default auth. There are already sites that do this.
The only difference is that instead of sending an http request of
{ username = "MyUsername", Password = "MyPassword" }
changes to{ username = "MyUsername", Password = HashOf("MyPassword") }
- and the HashOf("MyPassword") effectively becomes your password. - So I don't know how that opens up a possibility for replay attack. There's not really any difference between replaying a ClearText auth request vs an pre-hashed auth request. - Because everything else server side stays the same(Not entirely auth related), but another approach of client side decryption is to handle decryption completely client site - meaning all your data is stored encrypted on the server, and the server sends you an encrypted container with your data that you decrypt client side. That's how Proton(Mail) works in a nutshell
Put simply, jt allows an attacker with a leaked database to use the hashed password as a password. In your original comment, it seemed like you were suggesting hashing only before transmission, on the client; but hashing both before and after would indeed patch that particular vulnerability. I don't know if there are potential problems with that strategy or not.
Here's potentially an opportunity for me to learn: how does such a service (like Proton Mail) perform this in a web browser without having access to the data necessary to decrypt all of the data it's sending? Since you can't count on a web browser to have the private key, do you send down an encrypted private key that can only be decrypted with the user's password? Is there some other way to do this that I'm not aware of?
Ok, that wasn't what I was suggesting, no. That would effectively make your password hash the password itself - and it would kinda be stored in PlainText on the server, if you skip the client auth and send that value to the server directly through the api or something
Yes, pretty much. I can't really find a good, detailed explanation from Proton how it exactly works, but LastPass uses the same zero-knowledge encryption approach - which they explained with some diagram here - with a good overview of the client/server separation of it's hashing.
Awesome. Thanks for the links and the info.
Given what I know about how computers accept user input, I am fascinated to hear what the alternative is.
You have the text input feed directly into the encryption layer without an intermediary variable. The plaintext data should never be passable to an accessible variable which it must be to send the plaintext password in the email because it's not an asynchronous process.
I'm surprised so many people are getting hung up on basic infosec.
Are you suggesting to do all this on the frontend before it goes to the backend?
If they can send you, your own password in plain text. That's already bad enough. Just not good practise.
The front end to backend traffic should be encrypted, hashing occurs on the backend. The backend should never have access to a variable with a plaintext password.
I'm going to have to stop replying because I don't have the time to run every individual through infosec 101.
I asked because what you're describing doesn't do much if you understand how common web frameworks and runtime environments work.
The framework needs to parse the HTTP request. That means holding the parameters in a variable somewhere just to arrange them in a datastructure for processing.
But let's ignore that and say we have some kind of system that stream parses the request right out of the buffer (which itself still needs to be held in memory for a bit, but let's ignore that), and when it matches a preconfigured password parameter, passes it directly to the hashing system and nowhere else. I don't think any framework in existence actually does this, but let's run with it.
We'll still need to pass that value by whatever the language uses for function passing. It will be in a variable at some point. Since we rarely write in C these days unless we have to, the variable doesn't go away in the system until the garbage collection runs. Most systems don't use ref counting (and I think it's a mistake to disregard the simplicity of ref counting so universally, but that's another discussion), so that could happen whenever the thread gets around to it.
But even if it runs in a timely fashion, the memory page now has to be released to the OS. Except most runtimes don't. First, the variable in question almost certainly was not the only thing on that page. Second, runtimes rarely, if ever, release pages back to the OS. They figure if you're using that much memory once, you'll probably do it again. Why waste time releasing a page just to make you spend more time getting it again?
And we're still not done. Let's say we do release the page. The OS doesn't zero it out. That old variable is still there, and it could be handed over to a completely different process. Due to Copy on Write, it won't be cleared until that other process tries to write it. In other words, it could still be read by some random process on the system.
And we haven't even mentioned what happens if we start swapping. IIRC, some Linux kernel versions in the 2.4 series decided to swap out to disk ahead of time, always having a copy of memory on disk. Even if you're not running such an ancient version, you have to consider that the kernel could do as it pleases. Yeah, now that var potentially has a long lifespan.
To do what you want, we would need to coordinate clearing the var from the code down through the framework, runtime, and kernel. All to protect against a hypothetical memory attack. Which are actually quite difficult to pull off in practice. It'd be easier to attack the client's machine in some way.
And on top of it, you're running around with an undeserved sense of superiority while it's clear you haven't actually thought this through.
Yes. I agree 100% with the things I can and I defer to your experience where I can't. I used to write proprietary networking protocols 20 years ago and that's the knowledge and experience I'm leaning on.
As a matter of practice we would ensure to process passwords by encrypting the datasteam directly from the input, and they were never unencrypted in handling, so as to protect against various system and browser vulnerabilities. It would be a big deal to have them accessible in plaintext beyond the user client, not to mention accessible and processable by email generation methods and insecure email protocols.
I think you're a liar
It's a good thing your opinion makes no difference then isn't it.
how long have you been a web developer? Because I've been doing it for six years and almost every web app I've ever seen uses http with TLS to send the plaintext password to the backend, where it's popped into a request var at the controller level, then passed as an instance var to the service level, salted, hashed and stored. This includes apps that have to submit themselves for HIPAA compliance because they deal with PHI.
25, I used to write proprietary networking protocols.
shit, I wonder why the protocol that's much more well-adopted than yours does things differently
Imagining thinking what's popular is best. Betamax, HD DVD, Firewire, Ogg Vorbis, PNG, Firefox, Linux, Lemmy and friends, would all like a chat.
Maybe I'm misunderstanding you, but backend servers will almost always have the user-submitted password in plaintext as a variable, accessible to the backend server and any upstream proxies.
It's even how it's done in Lemmy. The bcrypt verify accepts the plaintext password and the expected salted hash.
There are ways to have passwords transmitted completely encrypted, but it involves hitting the backend for a challenge, then using that challenge to encrypt the password client side before sending. It still gets decrypted on the backend tho before hash and store.
Yeah, but SSL/TLS also solves that problem in a standardized way.
In either case, the backend will have the plaintext password regardless of how it's transmitted.
Yes, which is why they're vulnerable to mitm and local sniffer attacks.
Have you found a mitm attack on TLS?
This guy's a fucking clown, I'm sure he's like 15
Not without compromised certificates they haven't. You can tell because if they did they'd be world famous for having destroyed any and all internet security. Then again, they'd probably already be famous for having figured out a way to salt, hash and store passwords without ever holding them in memory first like they claim to do above, so maybe someone is lying on the internet about their vague "proprietary network protocols".
Oh yeah, this guy is a hoot.
I haven't looked into it but I was wondering about the logistics of setting up a federated honeypot for server side stream sniffing to build a plaintext email/password database.
Man, you sound like you're just using random words you heard in class. Clearly you have no clue how user registration actually works, let alone backend development.
Well it's a good thing your opinion has no effect on reality.
Sorry, but you're missing the point here. You cannot do anything with a password without storing it in memory. That's not even infosec 101, that's computing 101. Every computation is toggling bits between 1 and 0 and guess where these bits are stored? That's right: in memory.
You know how the backend gets that password? In a plaintext variable. Because the server needs to decrypt the TLS data before doing any computations on it (and yes I know about homomorphic encryption, but no that wouldn't work here).
Yes, I agree it's terrible form to send out plain text passwords. And it would make me question their security practices as well. I agree that lots of people overreacted to your mistake, but this thread has proven that you're not yet as knowledgeable as you claim to be.
You encrypt the datastream from the text input on the client side before storing it in a variable. It's not rocket science. I did this shit 20 years ago. Letting a plaintext password leave the user client is fucking stupid.