Hi @teddyphreak,
Thanks for the report.
We are able to reproduce the issue on unbuntu 16.04. The issue comes from the php extension gnupg provided by the official repo. We just tried to install the extension via pecl, and it solve the issue.
We proceed as following :
sudo apt-get remove php-gnupg
sudo apt-get install php-dev pear libpgpme11-dev
sudo pecl install gnupg
Ensure the extension is enabled for your cli and for your php-fpm (or whatever flavor you are using).
Let us know how it goes on your side.