Always sanitize coupon code to prevent inconsistent between admins and shop owners

includes/class-wc-cart.php

@@ -1691,7 +1691,7 @@ public function remove_coupons( $deprecated = null ) {
 	 */
 	public function remove_coupon( $coupon_code ) {
 		$coupon_code = wc_format_coupon_code( $coupon_code );
-		$position    = array_search( $coupon_code, $this->get_applied_coupons(), true );
+		$position    = array_search( $coupon_code, array_map( 'wc_format_coupon_code', $this->get_applied_coupons() ), true );
 
 		if ( false !== $position ) {
 			unset( $this->applied_coupons[ $position ] );

includes/class-wc-install.php

@@ -153,6 +153,10 @@ class WC_Install {
 			'wc_update_440_insert_attribute_terms_for_variable_products',
 			'wc_update_440_db_version',
 		),
+		'4.5.0' => array(
+			'wc_update_450_sanitize_coupons_code',
+			'wc_update_450_db_version',
+		),
 	);
 
 	/**

includes/class-wc-post-data.php

@@ -255,6 +255,9 @@ public static function wp_insert_post_data( $data ) {
 			}
 		} elseif ( 'product' === $data['post_type'] && 'auto-draft' === $data['post_status'] ) {
 			$data['post_title'] = 'AUTO-DRAFT';
+		} elseif ( 'shop_coupon' === $data['post_type'] ) {
+			// Coupons should never allow unfiltered HTML.
+			$data['post_title'] = wp_filter_kses( $data['post_title'] );
 		}
 
 		return $data;

includes/data-stores/class-wc-coupon-data-store-cpt.php

@@ -721,7 +721,7 @@ public function get_ids_by_code( $code ) {
 		return $wpdb->get_col(
 			$wpdb->prepare(
 				"SELECT ID FROM $wpdb->posts WHERE post_title = %s AND post_type = 'shop_coupon' AND post_status = 'publish' ORDER BY post_date DESC",
-				$code
+				wc_sanitize_coupon_code( $code )
 			)
 		);
 	}

includes/wc-formatting-functions.php

@@ -375,7 +375,7 @@ function wc_format_coupon_code( $value ) {
  * @return string
  */
 function wc_sanitize_coupon_code( $value ) {
-	return sanitize_post_field( 'post_title', $value, 0, 'db' );
+	return wp_filter_kses( sanitize_post_field( 'post_title', $value, 0, 'db' ) );
 }
 
 /**

includes/wc-update-functions.php

@@ -2175,3 +2175,70 @@ function wc_update_440_insert_attribute_terms_for_variable_products() {
 function wc_update_440_db_version() {
 	WC_Install::update_db_version( '4.4.0' );
 }
+
+/**
+ * Update DB version to 4.5.0.
+ */
+function wc_update_450_db_version() {
+	WC_Install::update_db_version( '4.5.0' );
+}
+
+/**
+ * Sanitize all coupons code.
+ *
+ * @return bool True to run again, false if completed.
+ */
+function wc_update_450_sanitize_coupons_code() {
+	global $wpdb;
+
+	$coupon_id      = 0;
+	$last_coupon_id = get_option( 'woocommerce_update_450_last_coupon_id', '0' );
+
+	$coupons = $wpdb->get_results(
+		$wpdb->prepare(
+			"SELECT ID, post_title FROM $wpdb->posts WHERE ID > %d AND post_type = 'shop_coupon' LIMIT 10",
+			$last_coupon_id
+		),
+		ARRAY_A
+	);
+
+	if ( empty( $coupons ) ) {
+		delete_option( 'woocommerce_update_450_last_coupon_id' );
+		return false;
+	}
+
+	foreach ( $coupons as $key => $data ) {
+		$coupon_id = intval( $data['ID'] );
+		$code      = trim( wp_filter_kses( $data['post_title'] ) );
+
+		if ( ! empty( $code ) && $data['post_title'] !== $code ) {
+			$wpdb->update(
+				$wpdb->posts,
+				array(
+					'post_title' => $code,
+				),
+				array(
+					'ID' => $coupon_id,
+				),
+				array(
+					'%s',
+				),
+				array(
+					'%d',
+				)
+			);
+
+			// Clean cache.
+			clean_post_cache( $coupon_id );
+			wp_cache_delete( WC_Cache_Helper::get_cache_prefix( 'coupons' ) . 'coupon_id_from_code_' . $data['post_title'], 'coupons' );
+		}
+	}
+
+	// Start the run again.
+	if ( $coupon_id ) {
+		return update_option( 'woocommerce_update_450_last_coupon_id', $coupon_id );
+	}
+
+	delete_option( 'woocommerce_update_450_last_coupon_id' );
+	return false;
+}

tests/legacy/framework/class-wc-unit-test-case.php

@@ -171,9 +171,9 @@ public function login_as_role( $role ) {
 	 */
 	public function login_as_administrator() {
 		return $this->login_as_role( 'administrator' );
-  }
+	}
 
-  /**
+	/**
 	 * Get an instance of a class that has been registered in the dependency injection container.
 	 * To get an instance of a legacy class (such as the ones in the 'íncludes' directory) use
 	 * 'get_legacy_instance_of' instead.

tests/php/includes/class-wc-post-data-test.php

@@ -0,0 +1,35 @@
+<?php
+/**
+ * Post data tests
+ *
+ * @package WooCommerce\Tests\Post_Data.
+ */
+
+/**
+ * Class WC_Post_Data_Test
+ */
+class WC_Post_Data_Test extends \WC_Unit_Test_Case {
+
+	/**
+	 * @testdox coupon code should be always sanitized.
+	 */
+	public function test_coupon_code_sanitization() {
+		$this->login_as_role( 'shop_manager' );
+		$coupon    = WC_Helper_Coupon::create_coupon( 'a&a' );
+		$post_data = get_post( $coupon->get_id() );
+		$this->assertEquals( 'a&amp;a', $post_data->post_title );
+		$coupon->delete( true );
+
+		$this->login_as_administrator();
+		$coupon    = WC_Helper_Coupon::create_coupon( 'b&b' );
+		$post_data = get_post( $coupon->get_id() );
+		$this->assertEquals( 'b&amp;b', $post_data->post_title );
+		$coupon->delete( true );
+
+		wp_set_current_user( 0 );
+		$coupon    = WC_Helper_Coupon::create_coupon( 'c&c' );
+		$post_data = get_post( $coupon->get_id() );
+		$this->assertEquals( 'c&amp;c', $post_data->post_title );
+		$coupon->delete( true );
+	}
+}

tests/php/includes/wc-formatting-functions-test.php

@@ -0,0 +1,20 @@
+<?php
+/**
+ * Formatting functions tests
+ *
+ * @package WooCommerce\Tests\Formatting.
+ */
+
+/**
+ * Class WC_Formatting_Functions_Test
+ */
+class WC_Formatting_Functions_Test extends \WC_Unit_Test_Case {
+
+	/**
+	 * Test wc_sanitize_coupon_code() function.
+	 */
+	public function test_wc_sanitize_coupon_code() {
+		$this->assertEquals( 'DUMMYCOUPON', wc_sanitize_coupon_code( 'DUMMYCOUPON' ) );
+		$this->assertEquals( 'a&amp;a', wc_sanitize_coupon_code( 'a&a' ) );
+	}
+}