diff --git a/src/json_html_serializer.cpp b/src/json_html_serializer.cpp
index 3e0e5f8..df34e2b 100644
--- a/src/json_html_serializer.cpp
+++ b/src/json_html_serializer.cpp
@@ -492,6 +492,10 @@
         {
             out += '\"';
             const std::string* ptr = val.get_ptr<const std::string*>();
+            if (ptr == nullptr)
+            {
+                return;
+            }
             dumpEscaped(out, *ptr);
             out += '\"';
             return;