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> self-signed was never trusted The whole problem of a self-signed cert is unless you have a priori knowledge of the cert somehow, it then is trivial to MITM a
by kop316 6y ago
> self-signed was never trusted
The whole problem of a self-signed cert is unless you have a priori knowledge of the cert somehow, it then is trivial to MITM a self-signed cert. That is why it was never trusted. That is the point of a signed cert, you are inherently trusting a third party to tell you the cert a website is giving you is good.
It does bring up an idea of making an individual a CA (i.e. you know someone's PGP key and that PGP key signs a cert, and that is a way to trust it). But you still fallback on the same issues with PGP email, you ultimately need someway of trusting it in the first place.
- pmlnr 6y agoSelf signed is more, than enough for the same purpose certbot exists: to have encrypted communication.
- pilsetnieks 6y agoThat is only one, the most basic purpose and the only that self-signed certificates can do. LE and other certificate authorities* at least prove that your data wasn't tampered with in transit, or wasn't decrypted, read and reencrypted without any way for you to find out. * as long as you trust those authorities
- deleted 6y ago[deleted]
- kop316 6y agoHow do you verify the cert then? If you can't verify the cert, you have no way to know it is not being man in the middled.
- fortran77 6y agoHow about putting some hash of the self-signed cert in a DNS TXT field?
- PeterisP 6y agoSelf-signed certs don't protect against active man in the middle attacks, but they do establish an encrypted channel that is secure against passive eavesdropping and after-the-fact decryption of network captures. So there's still some security benefit there.
- kerkeslager 6y agoThere really isn't a real-world situation I can think of where I'd care about passive eavesdropping or after-the-fact decryption and not also care about active eavesdropping. So I'm going to disagree. No, there is no security benefit to encryption without authentication.
- PeterisP 6y agoWhile the impact of all these things are the same, the likelihood is not. There certainly are real world situations where the chance of active eavesdropping (which requires a targeted attack, and is risky because it can be detected) is low, so you accept that level of risk, but the ability for someone to just grab all the traffic of a large group (that just happens to include you) for a prolonged period of time undetected is much higher.
- kerkeslager 6y agoThat's a good point. I may be wrong--I'll have to consider this a bit more.
- dtech 6y agoYou don't, but I don't like that mindset that an unverified certificate is somehow not better or even worse (see browser UIs) than no encryption. Encryption prevents sniffing, Encryption + trust prevents sniffing and MITM. Providing sniffing protection is an upgrade. As an example, say HTTP would always upgrade to HTTPS with a server provided public key. That would be more secure than the HTTP we have today, even though it wouldn't prevent MITM.
- skrebbel 6y agoI don't understand, anyone who can MITM can also sniff, right?
- kop316 6y agoYes they can. They simply decrypt, and reencrypt with their own self signed cert. If you have no way to verify the self-signed cert, you would never know.
- naniwaduni 6y agoAn adversary with MitM capability needs to commit to being detectable in order to read encrypted traffic.
- dtech 6y agobut not everyone who can sniff can MITM, encryption always prevents sniffing
- jackewiehose 6y ago> I don't like that mindset that an unverified certificate is somehow not better or even worse (see browser UIs) than no encryption Of course it's worse when the user thinks the connection is encrypted when he actually has no idea who he's talking to. What kind of attack do you have in mind where someone can sniff on the data but not tamper with it? And how should a browser explain this situation to the user? No, the mindset that an unverified certificate is better than no encryption is very dangerous.
- deleted 6y ago[deleted]
- tasuki 6y agoDANE could make CAs obsolete, and the internet more secure: https://en.wikipedia.org/wiki/DNS-based_Authentication_of_Named_Entities https://en.wikipedia.org/wiki/DNS-based_Authentication_of_Na...
- snowwrestler 6y agoIt just moves the basis of trust from a diverse network of private CAs, any of which can be individually punished or distrusted if they misbehave, to the single centralized system of DNS, which rolls up to whomever controls your TLD of choice--entities who usually can't be removed, punished, or replaced.
- tasuki 6y agoThere's a blockchain project that attempts to decentralize TLDs - people would actually own their TLDs (by cryptography!), and would issue their own certificates. Only you and no one else would be able to issue a certificate for your TLD. I've been shilling for this project enough, and feel it's a little offtopic here, but if you're really interested you can find it in my recent post history :)
- naniwaduni 6y agoEntities who also can de facto pull enough strings to authenticate to any CA as you, even under the existing system.
- Avamander 6y agoFrankly, that's bullshit. Now you have to trust your country or some other private entity, without all the protection mechanisms modern Web PKI has.
- toast0 6y agoLets Encrypt (and most other issuers) are happy to issue certificates to whoever controls the DNS for a domain, which could be your TLD administrator at their whim. I don't think DANE is going to make any progress, but opposing it because it gives TLDs more power is kind of bunk -- the TLDs already have that much power, DANE just makes it more explicit.