diff --git a/core/lib/Drupal/Component/Serialization/YamlPecl.php b/core/lib/Drupal/Component/Serialization/YamlPecl.php
index 2383bf8..fcc5f80 100644
--- a/core/lib/Drupal/Component/Serialization/YamlPecl.php
+++ b/core/lib/Drupal/Component/Serialization/YamlPecl.php
@@ -18,6 +18,9 @@ public static function encode($data) {
       ini_set('yaml.output_indent', 2);
       // Do not break lines at 80 characters.
       ini_set('yaml.output_width', -1);
+      // Decode binary, since Symfony YAML parser encodes binary from 3.1
+      // onwards.
+      ini_set('yaml.decode_binary', 1);
       $init = TRUE;
     }
     return yaml_emit($data, YAML_UTF8_ENCODING, YAML_LN_BREAK);