diff --git a/src/wp-includes/customize/class-wp-customize-color-control.php b/src/wp-includes/customize/class-wp-customize-color-control.php
index 1e7ed17786..8d9827351a 100644
--- a/src/wp-includes/customize/class-wp-customize-color-control.php
+++ b/src/wp-includes/customize/class-wp-customize-color-control.php
@@ -91,8 +91,7 @@ class WP_Customize_Color_Control extends WP_Customize_Control {
 		?>
 		<# var defaultValue = '#RRGGBB', defaultValueAttr = '',
 			isHueSlider = data.mode === 'hue';
-
-		if ( data.defaultValue && ! isHueSlider ) {
+		if ( data.defaultValue && _.isString( data.defaultValue ) && ! isHueSlider ) {
 			if ( '#' !== data.defaultValue.substring( 0, 1 ) ) {
 				defaultValue = '#' + data.defaultValue;
 			} else {