you need to configure the path of ckeditor file upload handler.
here’s the basic configuration code that can be used to insert a CKEditor instance with the file browser configured. (copied from documentation).
CKEDITOR.replace( ‘editor1’,
{
filebrowserBrowseUrl : ‘/browser/browse.php’, // File browser handler
filebrowserUploadUrl : ‘/uploader/upload.php’ // File Upload Handler
});
you may refer here for more in detail:
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