The transition to Post-Quantum Cryptography in the #Tor network's #TLS layer is making progress! 😎 We are now at 44.57% of Tor relays supporting the X25519MLKEM768 hybrid handshake. This number is up from 34.65% in March earlier this year.

I've uploaded a list of relays and their scan results from yesterday on https://ahf.me/tor-tls-pqc/2026-06-18/ and wrote an email to the tor-relays@ mailing-list summarising the results in https://lists.torproject.org/mailman3/hyperkitty/list/[email protected]/message/IY7FJU5XDSZ2O4SKUTN5VJFRLBRHYZ6W/

I hope we can get these numbers up in the near future. This upgrade requires more from the relay operators than our usual upgrades, as it depends upon an operating system-level upgrade of the underlying crypto libraries.

Now that #LibreSSL also supports the hybrid handshake, we also need to roll a C Tor release that enables the PQC group when Tor's compiled against LibreSSL. I will take a look at that next week! This should enable PQC for our #OpenBSD based Tor relays.

Thanks to all the relay operators for keeping their relays up to date! 🥳

#cryptography #postquantumcryptography #pqc