There are some commercial Certificate Authorities that offer free certificates. But in contrast Let's Encrypt is a non-profit.
- ZeroSSL (Austria)
- Actalis (Italy)
There are some commercial Certificate Authorities that offer free certificates. But in contrast Let's Encrypt is a non-profit.
Is anyone wonders why it's a problem it's under US juristriction:
Look up the US Cloud Act. It's everything the media told you China was, but in the hands of an orange dictator.
They have strong canaries in place, namely certificate transparency. They wisely designed themselves in a way to prevent themselves from tampering.
Well, honestly?
Since these certificates are not banned nor up for debate, the NSA probably already have a way to get all the data through another loop hole.
Yes, it protects against "attacks" from outside, but it's naive to expect they dont have another way in which goes beyond LetsEncrypt.
That loophole is Google and probably cloudflare. Google has their own DNS service, a script tag on nearly every website, half the mobile phone market while being the default search engine on the other half, and provides email to the majority of people. Even if you try not to use their services, they still have an enormous amount of information about you.
Any Govt agency with sufficient power can go to LetsEncrypt and have them either decrypt everything or issue specific certificates that can be decrypted and transparently allow man in the middle monitoring. That so much of the internet is using LetsEncrypt makes it highly likely this is all going on. It's technically possible and the Govt wouldn't allow LetsEncrypt to operate without being able to do this. Really this is true with all devices and encryption allowed to be sold. Unless you secretly meet all their demands they control all the required certifications and access to be able to sell your products, list them on the app stores, etc. It's just a good rule of thumb to consider everything has this starting point unless you design and build the entire hardware and software stack to ensure nothing like this can be done. But you'll never be able to sell it.
Fortunately, that's not how it works.
The private key is created on your server, not by Let's encrypt, and it's never transferred to them. Nobody can decrypt your data.
Certbot (the official ACME client) is open source, but you're also welcome to use any other client of your choosing, or make your own. The secrets never leave your server.
Unless the NSA has working powerful quantum computers that can break public key encryption, that they are successfully hiding from the public, they wouldn't be able to break let's encrypt certificates backed public key encryption, the math just doesn't math. It would still take the most powerful super computers millions of years to break RSA 2048.
There's a reason they want to make encryption illegal, instead of just letting us trust it like sheep. Thankfully, we don't have to trust anyone, it's all verifiable math.
You're not understanding Certificate Authorities or what certificate pinning does to stop man in the middle impersonation of firewall traffic. You have no understanding of what the Government is able to do to your devices and internet connection. You don't have to take my word for it, I don't care what you think. You just haven't been a target to understand.
'Muricans are so racist, we heard "orange chicken" and thought they were talking about China. 🤣
I do think we'll end up scrambling for alternatives at some point, so better to do it now.
Simi-related fun fact.
The biggest contributor to TOR is the CIA. They funded it's creation and are primarily responsible for maintaining it to this day.
The CIA maintains TOR as a way for spies to pass information over the internet. They make it public because if only spies used TOR it would be trivial to catch them. So it's in their interest that it be public and secure. It's open source and security experts agree you can trust it.
I thougnt it was the Navy, not CIA itself
So since this, according yo you, is a fact, I do suppose you have evidence to this claim? And I'm talking evidence that can be corroborated, not a Facebook post or something from a conspiracy sub, and not "oh man, everybody knows this!" because everybody doesn't know this.
Crazy that you’re downvoted for asking for sources lol
What risk are you trying to mitigate, specifically?
If it's the CA taking over your site, control over your CA specifically doesn't really give any advantage to an attacker (they would have to hijack traffic and provide a new certificate - nobody will notice if the certificate is from a different CA).
Note that your CA cannot decrypt the exchanges between your server and its clients.
It opens the possibility of a man-in-the-middle attack.
which is still there if you are not using lets encrypt, because they can strongarm them to make a fake cert for your domain, and install a proxy repackaging HTTPS traffic with the fake certificate. all browsers trust the lets encrypt root certificate, so they won't see anything suspicious.
the only thing there today to detect this (but not avoid) is certificate transparency logs. all modern certificates are required to be added to this log, for the CA to remain compliant. but browsers are not checking the logs, that would be a lot of additional traffic and how do they decide if a certificate was created maliciously? also, lets encrypt could afford being noncompliant, browser vendors can't realistically just distrust their root certificate, many sites would become inaccessible.
Oh snap! That definitely sounds possible. Found more info about it.
tl;dr: Either the attack is ineffective against some browsers that check the certificate transparency logs (like Chrome), or the attack is visible and the CA will lose all its credibility (hopefully being removed from the browsers).
it seems Firefox started doing the CT validation too, without needing to contact the CT log service: https://developer.mozilla.org/en-US/docs/Web/Security/Defenses/Certificate_Transparency#browser_requirements
and details: https://wiki.mozilla.org/SecurityEngineering/Certificate_Transparency
this sounds important:
This information has a 10 week expiration time. That is, if 10 weeks have passed since the information has been updated (typically by updating Firefox itself), the implementation will no longer enforce certificate transparency.
this also means, it can't truly verify SCT's that were issued since the last browser update?
Maybe I'm mistaken but aren't the logs cryptography verifiable? (As in you can't create a rouge cert without it creating a trace)
Edit: no, it doesn't. Looking at the comments below, it's public key crypto.
Original comment:
The problem is that if that is your threat model, then the VPS provider, ISP, and literally everything between you and letsencrypt can pull a conpromised key fro letsencrypt.
This actually happened btw, an xmpp server was attacked this way, they compromised not the server itself, but the VPS provider MITMed their traffic: https://www.devever.net/~hl/xmpp-incident
If your threat model involves this, then the only solution is Tor, which eliminates these requirements of trust.
Yep, that's what I described and any CA accepted by the client can do it
Are you sure they can't decrypt? They have your certificate after all. Besides, if the Orange has a bad day, he can ban certificates export or just for a single company or individual.
Edit: First two sentences were stupid, I apologize.
Yes, the private key never leaves your machine.
You send them a certificate signing request with your public key, they put their verification stamp on it and send it to you.
The only part they have to play is verifying that your certificate is trusted by a root certificate.
The CA cannot decypt: they don't have the secret key which only the server has. When requesting a new certificate from the CA, the server generated a secret key (aka private key) and then generated a derived public key that goes into a Certificate Signing Request (CSR). The CSR is what the CA receives, not the secret key, and then the CA returns the certificate file to the server, which has been endorsed by the CA and thus trusted by the user base.
Phrased another way, a certificate is the instrument that confirms that a purported public key can in-fact be safely used, and that no MITM attack is happening (assuming you trust the CA that signed the cert). But once you've confirmed the public key, the rest of the cryptography is public key cryptography, meaning the secrecy of the secret key is the whole game.
The certificate is only used for authentication. The actual data is encrypted with a temporary symmetric key that is generated via a diffie-hellman exchange
Even if they had your private key they still wouldn't be able to decrypt the data
A MITM doesn't require decrypting. It just requires telling a convincing enough lie to each side of a conversation that they think they're talking to the other party. Then you end up encrypting to their key which they can just read. That's different from breaking the encryption.
Are you sure they can’t decrypt?
No, and none of the state actors who do that kind of stuff will ever tell you. Watch The Imitation Game for a good/bad time and some context.
If you had a break for the modern crypto schemes and published it right now you would shut down all digital commerce, a lot of the spy traffic if not most of it^1^, and nothing could be started back up again until everything was redone from scratch. Best hope would be that the post quantum algorithms^2^ the cryptographers have aren't succeptible to whatever you did to break the existing algorithms. It'd take a bit to get the software implementations and keys in place, etc. The hardware stuff would take longer.
Quantum computers only threaten asymmetric ciphers, so every symmetric cipher is still safe, not just one-time-pads but things like AES and ChaCha20 aren't affected at all.
They don't have your private key
Let's encrypt is very transparent and has been designed to be auditable. What are you worried about exactly?
Still American. de-Americanizing the tech stack is a good idea.
Are you trying to solve a technica, or political/moral problem? Let's Encrypt doesn't create, see, store or log your private cerficates. So, even if they are in the US, I don't see a risk, and otherwise, the other parts you use in general are probably vulnerable to the problem even if non-US.
For ex. the US could simply order browsers stop validating any certificates not issues by US companies in browsers. And whoosh. Having a non-US certificate won't help much there either.
That the U.S. government can arbitrarily take down websites by revoking certificates issued by let's encrypt? How obvious can it be? I wondered the same thing as OP months ago. We need european alternatives. I think there are some, have some bookmarked somewhere.
Certificate revocation is a joke and has been for over a decade
Huh, FF on Android doesn't care.
Most browsers don't, hence my calling revocation a joke.
So many in this thread are up in arms about something the majority of browsers don't care about and have actively ignored for as long as I can recall
Yeah, I was just surprised bc the page explicitly lauds FF for checking revocation.
If the certificate only lasts two months revocation isn’t necessary, just deny recertification.
And what if you need to get a new certificate?
Orion browser (maybe safari?) on iOS detected the revoked certificate, and asked me to confirm before accessing the website while warning about the dangers.
Does regular safari show the same prompt? Afaik, browsers on iOS are safari reskins, so I'm curious if they added his cert in directly again, or if the onion browser actually follows standards the os browser doesn't.
Yes, but safari doesn't even let me ignore the warning, it has a explanation in detail, and only allows closing the website.
You didn’t look hard enough. My router cert isn’t valid and I have to bypass the warning every time.
Maybe there’s a special case for local subnets?
Here’s what shows up for me (in portuguese):

Clicking on more details, only allows me to check the certificate:

Here’s the translated details:
Safari warns you when a website has an invalid certificate. This can happen if an attacker has compromised your connection. For your protection, you cannot visit this site. You can check later to see if the problem has been solved. You can also contact the site owner to report this error.
To learn more, you can see the certificate.
Said certificate:

Edit: on the latest iOS version (27) btw.
uncle sam. audit away. until sam says “give me the keys” and then sam has the keys
@flandish @possiblylinux127 Letsencrypt just has the public keys, no private keys. If Letsencrypt gives my public keys to sam, it does not matter, because public keys are public. My private key is under my administration only.
and the backdoor?
@flandish Which backdoor? When I request a CA for a certificate, I send the public key to the CA. The CA does a validation and signs the certificate.The CA does not see any traffic from my server. A man-in-the-middle needs my private key, which is under my administration. If I loose my private key, it does not matter if the certificate is signed by a US based CA or an European CA.
@flandish If US authorities want to fake my server, they can use any CA, regardless which CA I originally used.Of course, US authorities can force Letsencrypt to revoke my certificates and block any renewing. This is very unlikely to happen. If it happens, I have to change my CA. There would be a downtime for my private services, but there is no data corruption or data loss on my servers.
@flandish This is no backdoor. This is an denial of service. It's a big difference. I have to estimate the risk and decide if I want to take it. ZeroSSL uses the infrastructure of Sectigo, an US company. Sectigo can pull the plug very easily. So it is no alternative. Maybe Actalis or Certum are good alternatives. But the government of Poland has not been unproblematic in the past.
Said backdoor isn't possible with the current day key exchange process. Without the servers in use private key, the most law agencies can do without acquiring the private key is force the CA to revoke a cert, which will disallow properly configured clients from accessing and transferring data with the server.
LE doesn't have enough information to recreate the private key based off the public key, the only key distributed during the CSR process is the servers public key via a certificate signing request which is signed using your private key, which the CA then signs with it's own intermediate key (which is signed by it's root server certificate) and hands back to the private server.
The CA doesn't have the ability to create that private key, and as such doesn't have a way to decrypt traffic that is using that key. There is no concern for a backdoor in that process.
In order for the "backdoor" to exist, they would need to either copy the private key as part of the signing process (which it doesn't), or somehow force the server admin to use a new private key (that the CA also holds) or somehow compromise the servers key generation process to allow for an escrow on the private key when it was generated which would allow the CA to be able to recreate the private key using the master & public key.
Now don't take me wrong, you can still have a MiTM impersonation attack or a full impersonation bypass by the CA issuing a new certificate and having the DNS registrar have the web address go to a new server that is using the new key but, that's not something the CA alone has the capability of doing, and any traffic that is issued to the original server still wouldn't be compromised, its just clients visiting your site will end up at the other site and as such will end up using keys that the other side generated instead of your own keys and additionally said new keys would also be appearing in Certificate transparency logs, or modern day clients would refuse to use them.
The transparency logs would mean that any rouge certificates created would leave a paper trail not to mention there is nothing stopping them from issuing a certificate for any domain of their choosing
I think Let's Encrypt will stay safe for quite a while, but unfortunately because of the political climate we're in right now, it may not stay safe in the future.
I don't think anyone is gonna solve that problem until it's actually a problem.
I don't think anyone's going to solve the problem in general, to be honest.
Like, Let's Encrypts goal is super novel, but also expensive as shit to actually run, and requires a lot of coordination because it needs to be a trust authority. If this ever happened, it would probably be at the backing of some government structure, because I don't see many people wanting to jump at that as an expense.
It is a problem, and there are solutions.
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