Multiple format string vulnerabilities in log_subscriber.rb files in the log subscriber component in Action Mailer in Ruby on Rails 3.x before 3.2.15 allow remote attackers to cause a denial of service via a crafted e-mail address that is improperly handled during construction of a log message.
Use of Externally-Controlled Format String The product uses a function that accepts a format string as an argument, but the format string originates from an external source.