RackEncodingScrubber

Removes invalid percent encodings, like:

ArgumentError: invalid %-encoding (%u00fcbersetzer)

Add this line to your application's Gemfile:

gem 'rack_encoding_scrubber'

And then execute:

$ bundle

Or install it yourself as:

$ gem install rack_encoding_scrubber

add to config/application.rb:

  config.middleware.insert_before "Rack::Runtime", "RackEncodingScrubber"