[0]https://protonmail.com/support/knowledge-base/protonmails-ss...
Why bother?
If they can MITM ProtonMail, they might as well use letsencrypt which just requires you control the domain name (for some definition of control).
> I'm not sure what the state of certificate pinning is,
Public-Key-Pins-Report-Only: pin-sha256="Jh0ZSUYEc97HRYcwZIOkH2jKOUpmQhLO48MYd1s5pRM="; pin-sha256="2ZnCTNQBrKShr4c1olKfwNG53KiL6qoNcQi65YGRBn8="; pin-sha256="1D76xWwHug9p4iQWVBiDZF+e3UcxtPte/ig5pkYnmRU="; max-age=300; report-uri="https://protonmail.com/pkp-report"
This is often used as an argument by EV advocates, but it doesn't hold up under scrutiny. An attacker with access to a non-EV certificate can selectively intercept only connections for subresources of the targeted site (i.e. JavaScript). The "main" connection would still use the EV certificate and thus show the browser indicator. This attack was first made public in 2008[1] and has been further refined in later work[2].
HPKP and the Expect-CT header provide some viable mitigations for this. That said, it seems unlikely to me that a nation-state adversary would choose to attack at the Web PKI level in this scenario. Compromising ProtonMail or the user's device would probably cheaper and less likely to be detected.
[1]: http://w2spconf.com/2008/papers/s2p1.pdf
[2]: https://www.blackhat.com/presentations/bh-usa-09/SOTIROV/BHU...
Switzerland is not an island of privacy with regard to state surveillance – and with regard to private data privacy, it basically mirrors the European Union’s standard. According to Snowden documents, Swiss intelligence and security services are close partners with the NSA and other foreign services.
Do you think that's partly because, like most countries, the truth is... obfuscated.
In other words, the law does not say that ProtonMail is exempt for having to provide lawful interception. They might still have to do so, based on some other law.
Further, it's quite conceivable that unlawful means (such as blackmail, threats, or bribery) could be used to coerce ProtonMail. That's not to mention perfectly lawful means of enticing them -- like appealing to their patriotism, willingness to help in a critical investigation, or demonstrating some credible threat.
> "Nearly every country in the world has laws governing lawful interception of electronic communications. In Switzerland, these regulations are set out in the Swiss Federal Act on the Surveillance of Postal and Telecommunications Traffic (SPTT) last revised in 2012. In the SPTT, the obligation to provide the technical means for lawful interception is imposed only on Internet access providers, so ProtonMail, as a mere Internet application provider, is completely exempt from the SPTT’s scope of application. This means that under Swiss law, ProtonMail cannot be compelled to backdoor our secure email system."
https://protonmail.com/blog/switzerland/