Hi all,
Devices running versions of Android older than 7.1.1 can't verify certificates signed with Let's Encrypt's ISRG Root X1 root certificate, so they can't connect to domain fronts that use such certificates. [1] These devices (released in 2016 or earlier) still make up nearly 5% of active Android devices. [2]
There was a workaround in place at one point -- cross-signing Let's Encrypt certificates with a different, expired root certificate and relying on Android not to check the expiry date -- but I believe the cross-signature expired in early 2024. [3]
With the loss of Fastly and Azure, the only remaining fronts for Meek and Snowflake in the default config served by Moat will be cdn77.com and phpmyadmin.net, both of which use Let's Encrypt certificates that are signed with ISRG Root X1 and don't appear to be cross-signed.
It looks like there's some work in progress to address this issue in Lyrebird by adding the relevant certificates, so hopefully Meek and Snowflake will work in a future Lyrebird release. But what about the initial connection to Moat?
Orbot has moved from Fastly to CDN77 for its Moat front [4]. Are there any plans underway to make another front available, or should we move to CDN77 and plan for Moat being unavailable on older Android devices?
Thanks, Michael
[1] https://letsencrypt.org/2020/11/06/own-two-feet/ [2] https://apilevels.com/ [3] https://arstechnica.com/gadgets/2020/12/lets-encrypt-comes-up-with-workaroun... [4] https://github.com/guardianproject/orbot/pull/1191/files