I cannot update to Joomla version 3.6.4 because core files have been changed. I am stuck at 3.4.6
I still want to protect against the vulnerabilities mentioned in https://www.joomla.org/announcements/release-news/5678-joomla-3-6-4-released.html
Are there alternatives to manually going through and merging the core files between my version and the fixed version?
We do have security plugins like RSFirewall installed.