diff --git a/include/Flow.h b/include/Flow.h
index 621782f245..df7caf0987 100644
--- a/include/Flow.h
+++ b/include/Flow.h
@@ -85,7 +85,8 @@ class Flow : public GenericHashEntry {
   ndpi_protocol ndpiDetectedProtocol;
   custom_app_t custom_app;
   void *cli_id, *srv_id;
-  char *json_info, *host_server_name, *bt_hash;
+  json_object *json_info;
+  char *host_server_name, *bt_hash;
   char *community_id_flow_hash;
 #ifdef HAVE_NEDGE
   u_int32_t last_conntrack_update; 
@@ -306,7 +307,7 @@ class Flow : public GenericHashEntry {
     return custom_app;
   };
   u_int16_t getStatsProtocol() const;
-  void setJSONInfo(const char *json);
+  void setJSONInfo(json_object *json);
 #ifdef NTOPNG_PRO
   inline bool is_status_counted_in_aggregated_flow()    const { return(status_counted_in_aggregated_flow); };
   inline bool is_counted_in_aggregated_flow()           const { return(counted_in_aggregated_flow);        };
@@ -360,7 +361,7 @@ class Flow : public GenericHashEntry {
   inline Host* get_srv_host()               const { return(srv_host);    };
   inline const IpAddress* get_cli_ip_addr() const { return(cli_ip_addr); };
   inline const IpAddress* get_srv_ip_addr() const { return(srv_ip_addr); };
-  inline char* get_json_info()	         const  { return(json_info);                       };
+  inline json_object* get_json_info()	    const  { return(json_info);                       };
   inline bool has_long_icmp_payload()    const  { return(protos.icmp.has_long_icmp_payload); };
   inline void set_long_icmp_payload()           { protos.icmp.has_long_icmp_payload = true;  };
   inline ndpi_protocol_breed_t get_protocol_breed() const {
diff --git a/src/Flow.cpp b/src/Flow.cpp
index cd258dd084..980419cbc5 100644
--- a/src/Flow.cpp
+++ b/src/Flow.cpp
@@ -62,7 +62,7 @@ Flow::Flow(NetworkInterface *_iface,
 
   ndpiFlow = NULL, cli_id = srv_id = NULL;
   cli_ebpf = srv_ebpf = NULL;
-  json_info = strdup("{}"), cli2srv_direction = true, twh_over = twh_ok = false,
+  json_info = NULL, cli2srv_direction = true, twh_over = twh_ok = false,
     dissect_next_http_packet = false,
     check_tor = false, host_server_name = NULL, diff_num_http_requests = 0,
     bt_hash = NULL, community_id_flow_hash = NULL;
@@ -221,7 +221,7 @@ Flow::~Flow() {
 
   if(last_partial)         free(last_partial);
   if(last_db_dump.partial) free(last_db_dump.partial);
-  if(json_info)            free(json_info);
+  if(json_info)            json_object_put(json_info);
   if(host_server_name)     free(host_server_name);
 
   if(cli_ebpf) delete cli_ebpf;
@@ -687,11 +687,14 @@ void Flow::setDetectedProtocol(ndpi_protocol proto_id, bool forceDetection) {
 
 /* *************************************** */
 
-void Flow::setJSONInfo(const char *json) {
+void Flow::setJSONInfo(json_object *json) {
   if(json == NULL) return;
 
-  if(json_info != NULL) free(json_info);
-  json_info = strdup(json);
+  if(json_info != NULL) 
+    json_object_put(json_info);
+
+  json_info = json;
+  json_object_get(json_info);
 }
 
 /* *************************************** */
@@ -1926,7 +1929,7 @@ void Flow::lua(lua_State* vm, AddressTree * ptree,
       }
     }
 
-    lua_push_str_table_entry(vm, "moreinfo.json", get_json_info());
+    lua_push_str_table_entry(vm, "moreinfo.json", get_json_info() ? json_object_to_json_string(get_json_info()) : "{}");
 
     if(cli_ebpf) processLua(vm, cli_ebpf, true);
     if(srv_ebpf) processLua(vm, srv_ebpf, false);
@@ -2300,21 +2303,11 @@ json_object* Flow::flow2json() {
   json_object_object_add(my_object, Utils::jsonLabel(LAST_SWITCHED, "LAST_SWITCHED", jsonbuf, sizeof(jsonbuf)),
 			 json_object_new_int((u_int32_t)get_partial_last_seen()));
 
-  if(json_info && strcmp(json_info, "{}")) {
-    json_object *o;
-    enum json_tokener_error jerr = json_tokener_success;
-
-    if((o = json_tokener_parse_verbose(json_info, &jerr)) != NULL) {
-      json_object_object_add(my_object, "json", o);
-    } else {
-      ntop->getTrace()->traceEvent(TRACE_INFO,
-				   "JSON Parse error [%s]: %s "
-				   " adding as a plain string",
-				   json_tokener_error_desc(jerr),
-				   json_info);
-      /* Experimental to attempt to fix https://github.com/ntop/ntopng/issues/522 */
-      json_object_object_add(my_object, "json", json_object_new_string(json_info));
-    }
+  if(json_info) {
+    bool json_info_empty = true;
+    json_object_object_foreach(json_info, key, val) { json_info_empty = false; break; }
+    if(!json_info_empty)
+      json_object_object_add(my_object, "json", json_info);
   }
 
   if(vlanId > 0) json_object_object_add(my_object,
diff --git a/src/NetworkInterface.cpp b/src/NetworkInterface.cpp
index f241a3b393..bba4c7f441 100644
--- a/src/NetworkInterface.cpp
+++ b/src/NetworkInterface.cpp
@@ -1374,7 +1374,7 @@ void NetworkInterface::processFlow(ParsedFlow *zflow, bool zmq_flow) {
   PROFILING_SECTION_EXIT(23);
 
   PROFILING_SECTION_ENTER("processFlow setJSONInfo", 24);
-  flow->setJSONInfo(json_object_to_json_string(zflow->additional_fields));
+  flow->setJSONInfo(zflow->additional_fields);
   PROFILING_SECTION_EXIT(24);
 
   PROFILING_SECTION_ENTER("processFlow local stats", 25);