diff --git a/rai/node/rpc.cpp b/rai/node/rpc.cpp
index 7d841de9..ea23f054 100644
--- a/rai/node/rpc.cpp
+++ b/rai/node/rpc.cpp
@@ -53,7 +53,8 @@ address (boost::asio::ip::address_v6::loopback ()),
 port (rai::rpc::rpc_port),
 enable_control (false),
 frontier_request_limit (16384),
-chain_request_limit (16384)
+chain_request_limit (16384),
+max_json_depth (20)
 {
 }
 
@@ -62,7 +63,8 @@ address (boost::asio::ip::address_v6::loopback ()),
 port (rai::rpc::rpc_port),
 enable_control (enable_control_a),
 frontier_request_limit (16384),
-chain_request_limit (16384)
+chain_request_limit (16384),
+max_json_depth (20)
 {
 }
 
@@ -73,6 +75,7 @@ void rai::rpc_config::serialize_json (boost::property_tree::ptree & tree_a) cons
 	tree_a.put ("enable_control", enable_control);
 	tree_a.put ("frontier_request_limit", frontier_request_limit);
 	tree_a.put ("chain_request_limit", chain_request_limit);
+	tree_a.put ("max_json_depth", max_json_depth);
 }
 
 bool rai::rpc_config::deserialize_json (boost::property_tree::ptree const & tree_a)
@@ -93,6 +96,7 @@ bool rai::rpc_config::deserialize_json (boost::property_tree::ptree const & tree
 			enable_control = tree_a.get<bool> ("enable_control");
 			auto frontier_request_limit_l (tree_a.get<std::string> ("frontier_request_limit"));
 			auto chain_request_limit_l (tree_a.get<std::string> ("chain_request_limit"));
+			max_json_depth = tree_a.get<uint8_t> ("max_json_depth", max_json_depth);
 			try
 			{
 				port = std::stoul (port_l);
@@ -3522,460 +3526,481 @@ void rai::rpc_handler::process_request ()
 {
 	try
 	{
-		std::stringstream istream (body);
-		boost::property_tree::read_json (istream, request);
-		std::string action (request.get<std::string> ("action"));
-		if (action == "password_enter")
-		{
-			password_enter ();
-			request.erase ("password");
-			reprocess_body (body, request);
-		}
-		else if (action == "password_change")
-		{
-			password_change ();
-			request.erase ("password");
-			reprocess_body (body, request);
-		}
-		else if (action == "wallet_unlock")
-		{
-			password_enter ();
-			request.erase ("password");
-			reprocess_body (body, request);
-		}
-		if (node.config.logging.log_rpc ())
-		{
-			BOOST_LOG (node.log) << boost::str (boost::format ("%1% ") % request_id) << body;
-		}
-		if (action == "account_balance")
-		{
-			account_balance ();
-		}
-		else if (action == "account_block_count")
-		{
-			account_block_count ();
-		}
-		else if (action == "account_count")
-		{
-			account_count ();
-		}
-		else if (action == "account_create")
-		{
-			account_create ();
-		}
-		else if (action == "account_get")
-		{
-			account_get ();
-		}
-		else if (action == "account_history")
-		{
-			account_history ();
-		}
-		else if (action == "account_info")
-		{
-			account_info ();
-		}
-		else if (action == "account_key")
-		{
-			account_key ();
-		}
-		else if (action == "account_list")
-		{
-			account_list ();
-		}
-		else if (action == "account_move")
-		{
-			account_move ();
-		}
-		else if (action == "account_remove")
-		{
-			account_remove ();
-		}
-		else if (action == "account_representative")
-		{
-			account_representative ();
-		}
-		else if (action == "account_representative_set")
-		{
-			account_representative_set ();
-		}
-		else if (action == "account_weight")
-		{
-			account_weight ();
-		}
-		else if (action == "accounts_balances")
-		{
-			accounts_balances ();
-		}
-		else if (action == "accounts_create")
-		{
-			accounts_create ();
-		}
-		else if (action == "accounts_frontiers")
-		{
-			accounts_frontiers ();
-		}
-		else if (action == "accounts_pending")
-		{
-			accounts_pending ();
-		}
-		else if (action == "available_supply")
-		{
-			available_supply ();
-		}
-		else if (action == "block")
-		{
-			block ();
-		}
-		else if (action == "block_confirm")
-		{
-			block_confirm ();
-		}
-		else if (action == "blocks")
-		{
-			blocks ();
-		}
-		else if (action == "blocks_info")
-		{
-			blocks_info ();
-		}
-		else if (action == "block_account")
-		{
-			block_account ();
-		}
-		else if (action == "block_count")
-		{
-			block_count ();
-		}
-		else if (action == "block_count_type")
-		{
-			block_count_type ();
-		}
-		else if (action == "block_create")
-		{
-			block_create ();
-		}
-		else if (action == "block_hash")
-		{
-			block_hash ();
-		}
-		else if (action == "successors")
-		{
-			chain (true);
-		}
-		else if (action == "bootstrap")
-		{
-			bootstrap ();
-		}
-		else if (action == "bootstrap_any")
-		{
-			bootstrap_any ();
-		}
-		else if (action == "chain")
-		{
-			chain ();
-		}
-		else if (action == "delegators")
-		{
-			delegators ();
-		}
-		else if (action == "delegators_count")
-		{
-			delegators_count ();
-		}
-		else if (action == "deterministic_key")
-		{
-			deterministic_key ();
-		}
-		else if (action == "confirmation_history")
-		{
-			confirmation_history ();
-		}
-		else if (action == "frontiers")
-		{
-			frontiers ();
-		}
-		else if (action == "frontier_count")
-		{
-			account_count ();
-		}
-		else if (action == "history")
-		{
-			request.put ("head", request.get<std::string> ("hash"));
-			account_history ();
-		}
-		else if (action == "keepalive")
-		{
-			keepalive ();
-		}
-		else if (action == "key_create")
-		{
-			key_create ();
-		}
-		else if (action == "key_expand")
-		{
-			key_expand ();
-		}
-		else if (action == "krai_from_raw")
-		{
-			mrai_from_raw (rai::kxrb_ratio);
-		}
-		else if (action == "krai_to_raw")
-		{
-			mrai_to_raw (rai::kxrb_ratio);
-		}
-		else if (action == "ledger")
-		{
-			ledger ();
-		}
-		else if (action == "mrai_from_raw")
-		{
-			mrai_from_raw ();
-		}
-		else if (action == "mrai_to_raw")
-		{
-			mrai_to_raw ();
-		}
-		else if (action == "password_change")
-		{
-			// Processed before logging
-		}
-		else if (action == "password_enter")
-		{
-			// Processed before logging
-		}
-		else if (action == "password_valid")
-		{
-			password_valid ();
-		}
-		else if (action == "payment_begin")
-		{
-			payment_begin ();
-		}
-		else if (action == "payment_init")
-		{
-			payment_init ();
-		}
-		else if (action == "payment_end")
-		{
-			payment_end ();
-		}
-		else if (action == "payment_wait")
-		{
-			payment_wait ();
-		}
-		else if (action == "peers")
-		{
-			peers ();
-		}
-		else if (action == "pending")
-		{
-			pending ();
-		}
-		else if (action == "pending_exists")
-		{
-			pending_exists ();
-		}
-		else if (action == "process")
-		{
-			process ();
-		}
-		else if (action == "rai_from_raw")
-		{
-			mrai_from_raw (rai::xrb_ratio);
-		}
-		else if (action == "rai_to_raw")
-		{
-			mrai_to_raw (rai::xrb_ratio);
-		}
-		else if (action == "receive")
-		{
-			receive ();
-		}
-		else if (action == "receive_minimum")
-		{
-			receive_minimum ();
-		}
-		else if (action == "receive_minimum_set")
-		{
-			receive_minimum_set ();
-		}
-		else if (action == "representatives")
-		{
-			representatives ();
-		}
-		else if (action == "representatives_online")
-		{
-			representatives_online ();
-		}
-		else if (action == "republish")
-		{
-			republish ();
-		}
-		else if (action == "search_pending")
-		{
-			search_pending ();
-		}
-		else if (action == "search_pending_all")
-		{
-			search_pending_all ();
-		}
-		else if (action == "send")
-		{
-			send ();
-		}
-		else if (action == "stats")
-		{
-			stats ();
-		}
-		else if (action == "stop")
-		{
-			stop ();
-		}
-		else if (action == "unchecked")
-		{
-			unchecked ();
-		}
-		else if (action == "unchecked_clear")
-		{
-			unchecked_clear ();
-		}
-		else if (action == "unchecked_get")
-		{
-			unchecked_get ();
-		}
-		else if (action == "unchecked_keys")
-		{
-			unchecked_keys ();
-		}
-		else if (action == "validate_account_number")
-		{
-			validate_account_number ();
-		}
-		else if (action == "version")
-		{
-			version ();
-		}
-		else if (action == "wallet_add")
-		{
-			wallet_add ();
-		}
-		else if (action == "wallet_add_watch")
-		{
-			wallet_add_watch ();
-		}
-		// Obsolete
-		else if (action == "wallet_balance_total")
-		{
-			wallet_info ();
-		}
-		else if (action == "wallet_balances")
-		{
-			wallet_balances ();
-		}
-		else if (action == "wallet_change_seed")
-		{
-			wallet_change_seed ();
-		}
-		else if (action == "wallet_contains")
-		{
-			wallet_contains ();
-		}
-		else if (action == "wallet_create")
-		{
-			wallet_create ();
-		}
-		else if (action == "wallet_destroy")
-		{
-			wallet_destroy ();
-		}
-		else if (action == "wallet_export")
-		{
-			wallet_export ();
-		}
-		else if (action == "wallet_frontiers")
-		{
-			wallet_frontiers ();
-		}
-		else if (action == "wallet_info")
-		{
-			wallet_info ();
-		}
-		else if (action == "wallet_key_valid")
-		{
-			wallet_key_valid ();
-		}
-		else if (action == "wallet_ledger")
-		{
-			wallet_ledger ();
-		}
-		else if (action == "wallet_lock")
-		{
-			wallet_lock ();
-		}
-		else if (action == "wallet_locked")
-		{
-			password_valid (true);
-		}
-		else if (action == "wallet_pending")
-		{
-			wallet_pending ();
-		}
-		else if (action == "wallet_representative")
-		{
-			wallet_representative ();
-		}
-		else if (action == "wallet_representative_set")
-		{
-			wallet_representative_set ();
-		}
-		else if (action == "wallet_republish")
-		{
-			wallet_republish ();
-		}
-		else if (action == "wallet_unlock")
-		{
-			// Processed before logging
-		}
-		else if (action == "wallet_work_get")
-		{
-			wallet_work_get ();
-		}
-		else if (action == "work_generate")
-		{
-			work_generate ();
-		}
-		else if (action == "work_cancel")
-		{
-			work_cancel ();
-		}
-		else if (action == "work_get")
-		{
-			work_get ();
-		}
-		else if (action == "work_set")
-		{
-			work_set ();
-		}
-		else if (action == "work_validate")
-		{
-			work_validate ();
-		}
-		else if (action == "work_peer_add")
-		{
-			work_peer_add ();
-		}
-		else if (action == "work_peers")
-		{
-			work_peers ();
-		}
-		else if (action == "work_peers_clear")
-		{
-			work_peers_clear ();
+		auto max_depth_exceeded (false);
+		auto max_depth_possible (0);
+		for (auto ch : body)
+		{
+			if (ch == '[' || ch == '{')
+			{
+				if (max_depth_possible >= rpc.config.max_json_depth)
+				{
+					max_depth_exceeded = true;
+					break;
+				}
+				++max_depth_possible;
+			}
+		}
+		if (max_depth_exceeded)
+		{
+			error_response (response, "Max JSON depth exceeded");
 		}
 		else
 		{
-			error_response (response, "Unknown command");
+			std::stringstream istream (body);
+			boost::property_tree::read_json (istream, request);
+			std::string action (request.get<std::string> ("action"));
+			if (action == "password_enter")
+			{
+				password_enter ();
+				request.erase ("password");
+				reprocess_body (body, request);
+			}
+			else if (action == "password_change")
+			{
+				password_change ();
+				request.erase ("password");
+				reprocess_body (body, request);
+			}
+			else if (action == "wallet_unlock")
+			{
+				password_enter ();
+				request.erase ("password");
+				reprocess_body (body, request);
+			}
+			if (node.config.logging.log_rpc ())
+			{
+				BOOST_LOG (node.log) << boost::str (boost::format ("%1% ") % request_id) << body;
+			}
+			if (action == "account_balance")
+			{
+				account_balance ();
+			}
+			else if (action == "account_block_count")
+			{
+				account_block_count ();
+			}
+			else if (action == "account_count")
+			{
+				account_count ();
+			}
+			else if (action == "account_create")
+			{
+				account_create ();
+			}
+			else if (action == "account_get")
+			{
+				account_get ();
+			}
+			else if (action == "account_history")
+			{
+				account_history ();
+			}
+			else if (action == "account_info")
+			{
+				account_info ();
+			}
+			else if (action == "account_key")
+			{
+				account_key ();
+			}
+			else if (action == "account_list")
+			{
+				account_list ();
+			}
+			else if (action == "account_move")
+			{
+				account_move ();
+			}
+			else if (action == "account_remove")
+			{
+				account_remove ();
+			}
+			else if (action == "account_representative")
+			{
+				account_representative ();
+			}
+			else if (action == "account_representative_set")
+			{
+				account_representative_set ();
+			}
+			else if (action == "account_weight")
+			{
+				account_weight ();
+			}
+			else if (action == "accounts_balances")
+			{
+				accounts_balances ();
+			}
+			else if (action == "accounts_create")
+			{
+				accounts_create ();
+			}
+			else if (action == "accounts_frontiers")
+			{
+				accounts_frontiers ();
+			}
+			else if (action == "accounts_pending")
+			{
+				accounts_pending ();
+			}
+			else if (action == "available_supply")
+			{
+				available_supply ();
+			}
+			else if (action == "block")
+			{
+				block ();
+			}
+			else if (action == "block_confirm")
+			{
+				block_confirm ();
+			}
+			else if (action == "blocks")
+			{
+				blocks ();
+			}
+			else if (action == "blocks_info")
+			{
+				blocks_info ();
+			}
+			else if (action == "block_account")
+			{
+				block_account ();
+			}
+			else if (action == "block_count")
+			{
+				block_count ();
+			}
+			else if (action == "block_count_type")
+			{
+				block_count_type ();
+			}
+			else if (action == "block_create")
+			{
+				block_create ();
+			}
+			else if (action == "block_hash")
+			{
+				block_hash ();
+			}
+			else if (action == "successors")
+			{
+				chain (true);
+			}
+			else if (action == "bootstrap")
+			{
+				bootstrap ();
+			}
+			else if (action == "bootstrap_any")
+			{
+				bootstrap_any ();
+			}
+			else if (action == "chain")
+			{
+				chain ();
+			}
+			else if (action == "delegators")
+			{
+				delegators ();
+			}
+			else if (action == "delegators_count")
+			{
+				delegators_count ();
+			}
+			else if (action == "deterministic_key")
+			{
+				deterministic_key ();
+			}
+			else if (action == "confirmation_history")
+			{
+				confirmation_history ();
+			}
+			else if (action == "frontiers")
+			{
+				frontiers ();
+			}
+			else if (action == "frontier_count")
+			{
+				account_count ();
+			}
+			else if (action == "history")
+			{
+				request.put ("head", request.get<std::string> ("hash"));
+				account_history ();
+			}
+			else if (action == "keepalive")
+			{
+				keepalive ();
+			}
+			else if (action == "key_create")
+			{
+				key_create ();
+			}
+			else if (action == "key_expand")
+			{
+				key_expand ();
+			}
+			else if (action == "krai_from_raw")
+			{
+				mrai_from_raw (rai::kxrb_ratio);
+			}
+			else if (action == "krai_to_raw")
+			{
+				mrai_to_raw (rai::kxrb_ratio);
+			}
+			else if (action == "ledger")
+			{
+				ledger ();
+			}
+			else if (action == "mrai_from_raw")
+			{
+				mrai_from_raw ();
+			}
+			else if (action == "mrai_to_raw")
+			{
+				mrai_to_raw ();
+			}
+			else if (action == "password_change")
+			{
+				// Processed before logging
+			}
+			else if (action == "password_enter")
+			{
+				// Processed before logging
+			}
+			else if (action == "password_valid")
+			{
+				password_valid ();
+			}
+			else if (action == "payment_begin")
+			{
+				payment_begin ();
+			}
+			else if (action == "payment_init")
+			{
+				payment_init ();
+			}
+			else if (action == "payment_end")
+			{
+				payment_end ();
+			}
+			else if (action == "payment_wait")
+			{
+				payment_wait ();
+			}
+			else if (action == "peers")
+			{
+				peers ();
+			}
+			else if (action == "pending")
+			{
+				pending ();
+			}
+			else if (action == "pending_exists")
+			{
+				pending_exists ();
+			}
+			else if (action == "process")
+			{
+				process ();
+			}
+			else if (action == "rai_from_raw")
+			{
+				mrai_from_raw (rai::xrb_ratio);
+			}
+			else if (action == "rai_to_raw")
+			{
+				mrai_to_raw (rai::xrb_ratio);
+			}
+			else if (action == "receive")
+			{
+				receive ();
+			}
+			else if (action == "receive_minimum")
+			{
+				receive_minimum ();
+			}
+			else if (action == "receive_minimum_set")
+			{
+				receive_minimum_set ();
+			}
+			else if (action == "representatives")
+			{
+				representatives ();
+			}
+			else if (action == "representatives_online")
+			{
+				representatives_online ();
+			}
+			else if (action == "republish")
+			{
+				republish ();
+			}
+			else if (action == "search_pending")
+			{
+				search_pending ();
+			}
+			else if (action == "search_pending_all")
+			{
+				search_pending_all ();
+			}
+			else if (action == "send")
+			{
+				send ();
+			}
+			else if (action == "stats")
+			{
+				stats ();
+			}
+			else if (action == "stop")
+			{
+				stop ();
+			}
+			else if (action == "unchecked")
+			{
+				unchecked ();
+			}
+			else if (action == "unchecked_clear")
+			{
+				unchecked_clear ();
+			}
+			else if (action == "unchecked_get")
+			{
+				unchecked_get ();
+			}
+			else if (action == "unchecked_keys")
+			{
+				unchecked_keys ();
+			}
+			else if (action == "validate_account_number")
+			{
+				validate_account_number ();
+			}
+			else if (action == "version")
+			{
+				version ();
+			}
+			else if (action == "wallet_add")
+			{
+				wallet_add ();
+			}
+			else if (action == "wallet_add_watch")
+			{
+				wallet_add_watch ();
+			}
+			// Obsolete
+			else if (action == "wallet_balance_total")
+			{
+				wallet_info ();
+			}
+			else if (action == "wallet_balances")
+			{
+				wallet_balances ();
+			}
+			else if (action == "wallet_change_seed")
+			{
+				wallet_change_seed ();
+			}
+			else if (action == "wallet_contains")
+			{
+				wallet_contains ();
+			}
+			else if (action == "wallet_create")
+			{
+				wallet_create ();
+			}
+			else if (action == "wallet_destroy")
+			{
+				wallet_destroy ();
+			}
+			else if (action == "wallet_export")
+			{
+				wallet_export ();
+			}
+			else if (action == "wallet_frontiers")
+			{
+				wallet_frontiers ();
+			}
+			else if (action == "wallet_info")
+			{
+				wallet_info ();
+			}
+			else if (action == "wallet_key_valid")
+			{
+				wallet_key_valid ();
+			}
+			else if (action == "wallet_ledger")
+			{
+				wallet_ledger ();
+			}
+			else if (action == "wallet_lock")
+			{
+				wallet_lock ();
+			}
+			else if (action == "wallet_locked")
+			{
+				password_valid (true);
+			}
+			else if (action == "wallet_pending")
+			{
+				wallet_pending ();
+			}
+			else if (action == "wallet_representative")
+			{
+				wallet_representative ();
+			}
+			else if (action == "wallet_representative_set")
+			{
+				wallet_representative_set ();
+			}
+			else if (action == "wallet_republish")
+			{
+				wallet_republish ();
+			}
+			else if (action == "wallet_unlock")
+			{
+				// Processed before logging
+			}
+			else if (action == "wallet_work_get")
+			{
+				wallet_work_get ();
+			}
+			else if (action == "work_generate")
+			{
+				work_generate ();
+			}
+			else if (action == "work_cancel")
+			{
+				work_cancel ();
+			}
+			else if (action == "work_get")
+			{
+				work_get ();
+			}
+			else if (action == "work_set")
+			{
+				work_set ();
+			}
+			else if (action == "work_validate")
+			{
+				work_validate ();
+			}
+			else if (action == "work_peer_add")
+			{
+				work_peer_add ();
+			}
+			else if (action == "work_peers")
+			{
+				work_peers ();
+			}
+			else if (action == "work_peers_clear")
+			{
+				work_peers_clear ();
+			}
+			else
+			{
+				error_response (response, "Unknown command");
+			}
 		}
 	}
 	catch (std::runtime_error const & err)
diff --git a/rai/node/rpc.hpp b/rai/node/rpc.hpp
index 49189c78..5b2bfe86 100644
--- a/rai/node/rpc.hpp
+++ b/rai/node/rpc.hpp
@@ -48,6 +48,7 @@ public:
 	uint64_t frontier_request_limit;
 	uint64_t chain_request_limit;
 	rpc_secure_config secure;
+	uint8_t max_json_depth;
 };
 enum class payment_status
 {