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I think maxk42 is worried about the TLS certificate root zone which contains many governments. Just look here [1] and search for "government", you'll find vario

by est31 8y ago

I think maxk42 is worried about the TLS certificate root zone which contains many governments. Just look here [1] and search for "government", you'll find various governments mentioned directly. Others are present indirectly, like the german government through the D-TRUST certificates that are operated by the 100% federally-owned company Bundesdruckerei. In the days before things like Certificate Transparency and HSTS preload lists, this was very worrysome because any of these governments could just freely impersonate any website they wanted to decrypt their access to. TLS is very vulnerable to this. SSH still has the TOFU model that is less vulnerable and TLS+TOFU is possible with HPKP but Chrome removed it. I can understand the reasons for the removal but it still had negative consequences. However, Google/Chrome is very avid about Certificate Transparency and many high-value domains are in the HSTS preload list with hardcoded CAs so we are in a better situation than just 5 years ago and I think it is going to improve going forward. So no reason to discard TLS entirely with some kind of nirvana fallacy, but of course, being aware of the problems is always a good thing. [1]: https://ccadb-public.secure.force.com/mozilla/IncludedCACertificateReport https://ccadb-public.secure.force.com/mozilla/IncludedCACert...

ggm 8y ago
Thanks. That was helpful. With letsencrypt it feels like this problem is not the problem it used to be, because most certificates are now self asserted.
- est31 8y ago
  While Letsencrypt is great, one more CA in the root zone isn't direct improvement of the situation. It's important to realize that any single CA in the root zone can, in theory, without asking anybody or doing anything else, create fake TLS certificates for any website they want and then subsequently use those certificates to perform Man-in-the-Middle attacks. You don't need to specifically trust the CA that signs the certificate of your website: they don't get your private key or anything, only the public key which everyone is getting. Instead, you need to trust every single CA in the root zone. That's at least the idea without certificate transparency (CT). The current SCT policy of Chrome for example increases [1, 2] the numbers of entities needed until a certificate is considered to be valid, and thus, any attack needs the cooperation of multiple such entities as well, making attacks harder to mount. [1]: https://www.entrustdatacard.com/blog/2018/february/chrome-requires-ct-after-april-2018 https://www.entrustdatacard.com/blog/2018/february/chrome-re... [2]: https://fpki.idmanagement.gov/announcements/chromect/ https://fpki.idmanagement.gov/announcements/chromect/
  - ggm 8y ago
    Again thanks. Most clear.
tialaramex 8y ago
Mozilla trusts eight "government" CA roots, associated with 5 countries in this list, China (Hong Kong), Spain, Taiwan, The Netherlands, and Turkey. The Turkish CA is constrained by Mozilla (and so in Firefox, but may not be constrained in your downstream software that wasn't written by Mozilla and just uses their trust lists wholesale) to just Turkish official sites, government, education, that sort of thing. The others are not subject to any notable constraints for a global CA. If you don't run Firefox or a Free Unix you probably trust a lot more government CAs. For example Microsoft's list includes 35 root CAs from Australia to Uruguay. It's hard to do a cursory up-to-the-minute examination of Apple's status because they provide a summary of information from the certificate itself which will often have been written by some nerd twenty years ago, leading to descriptions like "Government Root Certification Authority" and "CA Root" (those are both real examples from Apple's actual list) which don't tell a reader anything of value. I don't regard it as useful morally to try to count a company owned by the government as "the government". Consider the film production company Film 4. This is wholly owned by Channel 4, which is in turn wholly owned by the British government. So we could say the British government made "Four weddings and a funeral". OK, delightful English romantic comedy, sure, maybe drives tourism. "Trainspotting". Maybe it's a warning about how dangerous heroin is? "A Field In England" - Um, now we're struggling, I guess it is set in Britain at least. But wait, "The Motorcycle Diaries" is about the early life of Che Guevara, and "12 Years a Slave" is about a guy who was enslaved, in America. No, Film 4 is just a Film Prodution company, it happens to be owned by the British government, but that's even less relevant than which billionaire owns your favourite hockey team.

by est31 8y ago

ggm 8y ago

Thanks. That was helpful. With letsencrypt it feels like this problem is not the problem it used to be, because most certificates are now self asserted.

est31 8y ago
While Letsencrypt is great, one more CA in the root zone isn't direct improvement of the situation. It's important to realize that any single CA in the root zone can, in theory, without asking anybody or doing anything else, create fake TLS certificates for any website they want and then subsequently use those certificates to perform Man-in-the-Middle attacks. You don't need to specifically trust the CA that signs the certificate of your website: they don't get your private key or anything, only the public key which everyone is getting. Instead, you need to trust every single CA in the root zone. That's at least the idea without certificate transparency (CT). The current SCT policy of Chrome for example increases [1, 2] the numbers of entities needed until a certificate is considered to be valid, and thus, any attack needs the cooperation of multiple such entities as well, making attacks harder to mount. [1]: https://www.entrustdatacard.com/blog/2018/february/chrome-requires-ct-after-april-2018 https://www.entrustdatacard.com/blog/2018/february/chrome-re... [2]: https://fpki.idmanagement.gov/announcements/chromect/ https://fpki.idmanagement.gov/announcements/chromect/
- ggm 8y ago
  Again thanks. Most clear.

tialaramex 8y ago

Mozilla trusts eight "government" CA roots, associated with 5 countries in this list, China (Hong Kong), Spain, Taiwan, The Netherlands, and Turkey. The Turkish CA is constrained by Mozilla (and so in Firefox, but may not be constrained in your downstream software that wasn't written by Mozilla and just uses their trust lists wholesale) to just Turkish official sites, government, education, that sort of thing. The others are not subject to any notable constraints for a global CA. If you don't run Firefox or a Free Unix you probably trust a lot more government CAs. For example Microsoft's list includes 35 root CAs from Australia to Uruguay. It's hard to do a cursory up-to-the-minute examination of Apple's status because they provide a summary of information from the certificate itself which will often have been written by some nerd twenty years ago, leading to descriptions like "Government Root Certification Authority" and "CA Root" (those are both real examples from Apple's actual list) which don't tell a reader anything of value. I don't regard it as useful morally to try to count a company owned by the government as "the government". Consider the film production company Film 4. This is wholly owned by Channel 4, which is in turn wholly owned by the British government. So we could say the British government made "Four weddings and a funeral". OK, delightful English romantic comedy, sure, maybe drives tourism. "Trainspotting". Maybe it's a warning about how dangerous heroin is? "A Field In England" - Um, now we're struggling, I guess it is set in Britain at least. But wait, "The Motorcycle Diaries" is about the early life of Che Guevara, and "12 Years a Slave" is about a guy who was enslaved, in America. No, Film 4 is just a Film Prodution company, it happens to be owned by the British government, but that's even less relevant than which billionaire owns your favourite hockey team.