How about downgrading that glibc until there’s a fix?
The problem is in glibc version 2.23-0ubuntu6

apt-get -y --allow-downgrades install libc6=2.23-0ubuntu3

You’re probably hit by the latest security update from Ubuntu, which messed up some certificates, which PHP uses to make the secure connection.
https://www.ubuntu.com/usn/usn-3239-1/

Run this service php7.0-fpm restart and it should fix it. Or simply restart your server.
People running Apache, needs to restart that with service apache restart

We are getting that error too. After we restart the server it works, but it keep happening again.

Any idea how to fix this?

Thanks in advance