The mail gem before 2.5.5 for Ruby (aka A Really Ruby Mail Library) is vulnerable to SMTP command injection via CRLF sequences in a RCPT TO or MAIL FROM command, as demonstrated by CRLF sequences immediately before and after a DATA substring.
- https://github.com/rubysec/ruby-advisory-db/issues/215
- https://github.com/ARPSyndicate/cvemon