The is a code injection vulnerability in versions of Rails prior to 5.0.1 that wouldallow an attacker who controlled the `locals` argument of a `render` call to perform a RCE.
https://lists.debian.org/debian-lts-announce/2020/07/msg00013.html
https://hackerone.com/reports/304805
https://groups.google.com/g/rubyonrails-security/c/hWuKcHyoKh0
http://packetstormsecurity.com/files/158604/Ruby-On-Rails-5.0.1-Remote-Code-Execution.html