A directory traversal vulnerability exists in rack < 2.2.0 that allows an attacker perform directory traversal vulnerability in the Rack::Directory app that is bundled with Rack which could result in information disclosure.
https://usn.ubuntu.com/4561-1/
https://lists.debian.org/debian-lts-announce/2023/01/msg00038.html
https://lists.debian.org/debian-lts-announce/2020/07/msg00006.html
https://hackerone.com/reports/434404
https://groups.google.com/g/rubyonrails-security/c/IOO1vNZTzPA