/etc/nginx/snippets/snakeoil.conf is in nginx-common 1.6.2-5+deb8u5.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 | # Self signed certificates generated by the ssl-cert package
# Don't use them in a production server!
ssl_certificate /etc/ssl/certs/ssl-cert-snakeoil.pem;
ssl_certificate_key /etc/ssl/private/ssl-cert-snakeoil.key;
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