diff --git a/wp-includes/functions.php b/wp-includes/functions.php
index 5802a34146..40dec2c4a7 100644
--- a/wp-includes/functions.php
+++ b/wp-includes/functions.php
@@ -5227,8 +5227,9 @@ function _device_can_upload() {
  * @return bool True if the path is a stream URL.
  */
 function wp_is_stream( $path ) {
-	$wrappers = stream_get_wrappers();
-	$wrappers_re = '(' . join('|', $wrappers) . ')';
+	$wrappers    = stream_get_wrappers();
+	$wrappers    = array_map( 'preg_quote', $wrappers );
+	$wrappers_re = '(' . join( '|', $wrappers ) . ')';
 
 	return preg_match( "!^$wrappers_re://!", $path ) === 1;
 }
diff --git a/wp-includes/version.php b/wp-includes/version.php
index 481e37a3f5..109dae79cd 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.9.8-alpha-43482';
+$wp_version = '4.9.8-alpha-43483';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.