diff --git a/wp-includes/functions.php b/wp-includes/functions.php
index 9b5f292eec..320d76918e 100644
--- a/wp-includes/functions.php
+++ b/wp-includes/functions.php
@@ -5459,6 +5459,7 @@ function _device_can_upload() {
  */
 function wp_is_stream( $path ) {
 	$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 0e9efff0d6..937d54af6d 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '5.0-alpha-42431';
+$wp_version = '5.0-alpha-42432';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.