How to fix "Insecure world writable dir /mnt/c in PATH, mode 040777" error after running "rails s"

I tried changing the permissions but it's still not working. I created a new Rails app to test it and got the same error when I tried to start the Rails server.
And I get the same error when I run rails -v in the application folder.

How do I fix this?

rails s output:

/usr/lib/ruby/vendor_ruby/rails/app_rails_loader.rb:39: warning: Insecure world writable dir /mnt/c in PATH, mode 040777
    /usr/bin/ruby2.5: warning: shebang line ending with \r may cause problems
    Ignoring executable-hooks-1.6.0 because its extensions are not built. Try: gem pristine executable-hooks --version 1.6.0
    Ignoring gem-wrappers-1.4.0 because its extensions are not built. Try: gem pristine gem-wrappers --version 1.4.0       
    Ignoring nio4r-2.5.2 because its extensions are not built. Try: gem pristine nio4r --version 2.5.2
    Ignoring nokogiri-1.10.7 because its extensions are not built. Try: gem pristine nokogiri --version 1.10.7
    Ignoring websocket-driver-0.7.1 because its extensions are not built. Try: gem pristine websocket-driver --version 0.7.1
    Traceback (most recent call last):
            4: from bin/rails:3:in `<main>'
            3: from bin/rails:3:in `load'
            2: from /mnt/c/Users/max/Desktop/Dev/app_project/bin/spring:8:in `<top (required)>'
            1: from /usr/lib/ruby/2.5.0/rubygems/core_ext/kernel_require.rb:59:in `require'
    /usr/lib/ruby/2.5.0/rubygems/core_ext/kernel_require.rb:59:in `require': cannot load such file -- bundler (LoadError)

My Gemfile:

source 'https://rubygems.org'
git_source(:github) { |repo| "https://github.com/#{repo}.git" }

ruby '2.6.5'

gem 'rails', '~> 6.0.0'
gem 'sqlite3', '~> 1.4'
gem 'puma', '~> 3.11'
gem 'sass-rails', '~> 5'
gem 'webpacker', '~> 4.0'
gem 'turbolinks', '~> 5'
gem 'jbuilder', '~> 2.7'


gem 'bootsnap', '>= 1.4.2', require: false

group :development, :test do
  # Call 'byebug' anywhere in the code to stop execution and get a debugger console
  gem 'byebug', platforms: [:mri, :mingw, :x64_mingw]
end

group :development do
  gem 'web-console', '>= 3.3.0'
  gem 'listen', '>= 3.0.5', '< 3.2'
  gem 'spring'
  gem 'spring-watcher-listen', '~> 2.0.0'
  gem 'better_errors', '~> 2.5', '>= 2.5.1'
end

group :test do
  gem 'capybara', '>= 2.15'
  gem 'selenium-webdriver'
  gem 'webdrivers'
end

gem 'tzinfo-data', platforms: [:mingw, :mswin, :x64_mingw, :jruby]

gem 'bootstrap', '~> 4.4.1'

gem 'devise', '~> 4.7', '>= 4.7.1'
gem 'jquery-rails'
gem 'toastr-rails'

gem 'omniauth', '~> 1.9'

gem 'omniauth-facebook', '~> 5.0'

lsb_release -a output:

No LSB modules are available.
Distributor ID: Ubuntu
Description:    Ubuntu 18.04.2 LTS
Release:        18.04
Codename:       bionic

rvm list output:

=* ruby-2.6.5 [ x86_64 ]

# => - current
# =* - current && default
#  * - default

gem -v output:

3.1.2

ruby -v output:

ruby 2.6.5p114 (2019-10-01 revision 67812) [x86_64-linux]

I faced this issue on Windows 10 WSL, Ubuntu 18.04, and I solved it by:

• Opening or initializing wsl.conf file under the /etc folder like this: sudo nano /etc/wsl.conf
• Adding these two lines in the document:

[automount]
options="metadata,umask=0033" 

• Saving the document by: pressing CTRL+X shortcut, then pressing Y, then Enter key to confirm the changes
• Restarting my computer (Very important for changes to take effect)

References:

• Microsoft Dev Blog: Automatically Configuring WSL
• Github - Microsoft/WSL: warning: Insecure world writable dir /mnt/c in PATH, mode 040777 #1426

Are you using WSL?

Since C drive (/mnt/c) is a Windows partition it doesn't share the file/dir permission system from Ubuntu(Linux).

"warning: Insecure world writable dir /mnt/c in PATH, mode 040777 #1426" from WSL can be useful.

I encountered this on macOS while I was doing things with Cocoapods. sudo chmod 755 /your/directory helped me get rid of this issue. Hope it can work for you.