diff --git a/assets/js/frontend/add-to-cart-variation.js b/assets/js/frontend/add-to-cart-variation.js
index e4ee1241ad3..be56446a936 100644
--- a/assets/js/frontend/add-to-cart-variation.js
+++ b/assets/js/frontend/add-to-cart-variation.js
@@ -352,11 +352,19 @@
 								}
 
 								if ( attr_val ) {
-									// Decode entities and add slashes.
+									// Decode entities.
 									attr_val = $( '<div/>' ).html( attr_val ).text();
 
-									// Attach.
-									new_attr_select.find( 'option[value="' + form.addSlashes( attr_val ) + '"]' ).addClass( 'attached ' + variation_active );
+									// Attach to matching options by value. This is done to compare
+									// TEXT values rather than any HTML entities.
+									new_attr_select.find( 'option' ).each( function( index, el ) {
+										var option_value = $( this ).val();
+
+										if ( attr_val === option_value ) {
+											$( this ).addClass( 'attached ' + variation_active );
+											return false; // break.
+										}
+									});
 								} else {
 									// Attach all apart from placeholder.
 									new_attr_select.find( 'option:gt(0)' ).addClass( 'attached ' + variation_active );
@@ -371,8 +379,19 @@
 			attached_options_count = new_attr_select.find( 'option.attached' ).length;
 
 			// Check if current selection is in attached options.
-			if ( selected_attr_val && ( attached_options_count === 0 || new_attr_select.find( 'option.attached.enabled[value="' + form.addSlashes( selected_attr_val ) + '"]' ).length === 0 ) ) {
+			if ( selected_attr_val ) {
 				selected_attr_val_valid = false;
+
+				if ( 0 !== attached_options_count ) {
+					new_attr_select.find( 'option.attached.enabled' ).each( function( index, el ) {
+						var option_value = $( this ).val();
+
+						if ( selected_attr_val === option_value ) {
+							selected_attr_val_valid = true;
+							return false; // break.
+						}
+					});
+				}
 			}
 
 			// Detach the placeholder if:
diff --git a/includes/admin/meta-boxes/class-wc-meta-box-product-data.php b/includes/admin/meta-boxes/class-wc-meta-box-product-data.php
index 1219d40fcd6..f463f6af277 100644
--- a/includes/admin/meta-boxes/class-wc-meta-box-product-data.php
+++ b/includes/admin/meta-boxes/class-wc-meta-box-product-data.php
@@ -228,7 +228,7 @@ class WC_Meta_Box_Product_Data {
 		$attributes = array();
 
 		if ( ! $data ) {
-			$data = $_POST;
+			$data = stripslashes_deep( $_POST );
 		}
 
 		if ( isset( $data['attribute_names'], $data['attribute_values'] ) ) {
diff --git a/includes/class-wc-ajax.php b/includes/class-wc-ajax.php
index 10f2d397901..07036735d26 100644
--- a/includes/class-wc-ajax.php
+++ b/includes/class-wc-ajax.php
@@ -618,7 +618,7 @@ class WC_AJAX {
 		$response = array();
 
 		try {
-			parse_str( $_POST['data'], $data );
+			parse_str( wp_unslash( $_POST['data'] ), $data );
 
 			$attributes   = WC_Meta_Box_Product_Data::prepare_attributes( $data );
 			$product_id   = absint( $_POST['post_id'] );
diff --git a/includes/data-stores/class-wc-product-data-store-cpt.php b/includes/data-stores/class-wc-product-data-store-cpt.php
index c3b0b6c6b59..25a3c2ce211 100644
--- a/includes/data-stores/class-wc-product-data-store-cpt.php
+++ b/includes/data-stores/class-wc-product-data-store-cpt.php
@@ -764,7 +764,8 @@ class WC_Product_Data_Store_CPT extends WC_Data_Store_WP implements WC_Object_Da
 					);
 				}
 			}
-			update_post_meta( $product->get_id(), '_product_attributes', $meta_values );
+			// Note, we use wp_slash to add extra level of escaping. See https://codex.wordpress.org/Function_Reference/update_post_meta#Workaround.
+			update_post_meta( $product->get_id(), '_product_attributes', wp_slash( $meta_values ) );
 		}
 	}
 
diff --git a/includes/data-stores/class-wc-product-variation-data-store-cpt.php b/includes/data-stores/class-wc-product-variation-data-store-cpt.php
index 80aff7b5020..fc1e3c08085 100644
--- a/includes/data-stores/class-wc-product-variation-data-store-cpt.php
+++ b/includes/data-stores/class-wc-product-variation-data-store-cpt.php
@@ -428,7 +428,7 @@ class WC_Product_Variation_Data_Store_CPT extends WC_Product_Data_Store_CPT impl
 			$attributes             = $product->get_attributes();
 			$updated_attribute_keys = array();
 			foreach ( $attributes as $key => $value ) {
-				update_post_meta( $product->get_id(), 'attribute_' . $key, $value );
+				update_post_meta( $product->get_id(), 'attribute_' . $key, wp_slash( $value ) );
 				$updated_attribute_keys[] = 'attribute_' . $key;
 			}
 
diff --git a/includes/wc-attribute-functions.php b/includes/wc-attribute-functions.php
index 6a02dc278aa..d913d0da1c3 100644
--- a/includes/wc-attribute-functions.php
+++ b/includes/wc-attribute-functions.php
@@ -94,10 +94,10 @@ function wc_attribute_taxonomy_name_by_id( $attribute_id ) {
 	$attribute_name = $wpdb->get_var(
 		$wpdb->prepare(
 			"
-		SELECT attribute_name
-		FROM {$wpdb->prefix}woocommerce_attribute_taxonomies
-		WHERE attribute_id = %d
-	",
+			SELECT attribute_name
+			FROM {$wpdb->prefix}woocommerce_attribute_taxonomies
+			WHERE attribute_id = %d
+			",
 			$attribute_id
 		)
 	);
@@ -384,10 +384,10 @@ function wc_get_attribute( $id ) {
 	$data = $wpdb->get_row(
 		$wpdb->prepare(
 			"
-		SELECT *
-		FROM {$wpdb->prefix}woocommerce_attribute_taxonomies
-		WHERE attribute_id = %d
-	 ",
+			SELECT *
+			FROM {$wpdb->prefix}woocommerce_attribute_taxonomies
+			WHERE attribute_id = %d
+			",
 			$id
 		)
 	);
@@ -558,7 +558,7 @@ function wc_create_attribute( $args ) {
 				$unserialized_data[ $new_taxonomy_name ] = $unserialized_data[ $old_taxonomy_name ];
 				unset( $unserialized_data[ $old_taxonomy_name ] );
 				$unserialized_data[ $new_taxonomy_name ]['name'] = $new_taxonomy_name;
-				update_post_meta( $product_id, '_product_attributes', $unserialized_data );
+				update_post_meta( $product_id, '_product_attributes', wp_slash( $unserialized_data ) );
 			}
 
 			// Update variations which use this taxonomy.
@@ -625,10 +625,10 @@ function wc_delete_attribute( $id ) {
 	$name = $wpdb->get_var(
 		$wpdb->prepare(
 			"
-		SELECT attribute_name
-		FROM {$wpdb->prefix}woocommerce_attribute_taxonomies
-		WHERE attribute_id = %d
-	",
+			SELECT attribute_name
+			FROM {$wpdb->prefix}woocommerce_attribute_taxonomies
+			WHERE attribute_id = %d
+			",
 			$id
 		)
 	);