[shaunpersad]

Doubtful on Firebase. It's a managed service so it's not in the same category as these DBs, and is also authenticated by default.

[rockwotj]

I used to work on the Firebase realtime database - many people went to production with public reads/writes. We spent a lot of time trying to educate people not to do that.

Examples: https://www.comparitech.com/blog/information-security/fireba... and http://ghostlulz.com/google-exposed-firebase-database/