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Are there any security issues with AJAX?

  •  A JavaScript can not access the local file system without the user's permission. 
  •  An AJAX interaction can only be made with the servers-side component from which the page was loaded. 
  •  A proxy pattern could be used for AJAX interactions with external services. 
  •  The application model should not be exposed as some user might be able to reverse engineer the application. 
  •  HTTPS can be used to secure the connection when confidential information is being exchanged.