diff --git a/Utils/Parser/Markdown/Markdown.php b/Utils/Parser/Markdown/Markdown.php
index 98299afb3..d548f0d31 100755
--- a/Utils/Parser/Markdown/Markdown.php
+++ b/Utils/Parser/Markdown/Markdown.php
@@ -3914,7 +3914,7 @@ protected function element(array $Element)
                         continue;
                     }
 
-                    $markup .= " {$name}=\"".self::escape($value).'"';
+                    $markup .= " {$name}=\"".self::escape((string) $value).'"';
                 }
             }
         }