diff --git a/wp-includes/rest-api.php b/wp-includes/rest-api.php
index 9b023e97ec..242b317ca1 100644
--- a/wp-includes/rest-api.php
+++ b/wp-includes/rest-api.php
@@ -1304,6 +1304,9 @@ function rest_get_avatar_sizes() {
 /**
  * Parses an RFC3339 time into a Unix timestamp.
  *
+ * Explicitly check for `false` to detect failure, as zero is a valid return
+ * value on success.
+ *
  * @since 4.4.0
  *
  * @param string $date      RFC3339 timestamp.
@@ -1369,7 +1372,7 @@ function rest_get_date_with_gmt( $date, $is_utc = false ) {
 
 	$date = rest_parse_date( $date );
 
-	if ( empty( $date ) ) {
+	if ( false === $date ) {
 		return null;
 	}
 
@@ -2259,7 +2262,7 @@ function rest_validate_value_from_schema( $value, $args, $param = '' ) {
 				break;
 
 			case 'date-time':
-				if ( ! rest_parse_date( $value ) ) {
+				if ( false === rest_parse_date( $value ) ) {
 					return new WP_Error( 'rest_invalid_date', __( 'Invalid date.' ) );
 				}
 				break;
diff --git a/wp-includes/version.php b/wp-includes/version.php
index e4dd889496..0547ad31c1 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -16,7 +16,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '6.7-alpha-59039';
+$wp_version = '6.7-alpha-59040';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.