Hacker News Reader

> Running two production applications on 5.1.5.

I believe there are security vulnerabilities in that version. consider updating to a secure version: 5.1.7 is the latest revision of the 5.1.x series.

https://weblog.rubyonrails.org/2019/3/13/Rails-4-2-5-1-5-1-6...

View on HN

Also, the 5.1 series will not receive any future security fixes now that 6.0 is out.

So you could consider upgrading to 5.2 instead of 6.0. This is just one minor version step so should be less daunting. And 5.2 will receive security updates for a while yet.

Reply on news.ycombinator.com