diff --git a/dbms/programs/server/InterserverIOHTTPHandler.cpp b/dbms/programs/server/InterserverIOHTTPHandler.cpp
index 94095365b6a..27e4c7041c4 100644
--- a/dbms/programs/server/InterserverIOHTTPHandler.cpp
+++ b/dbms/programs/server/InterserverIOHTTPHandler.cpp
@@ -1,17 +1,16 @@
+#include "InterserverIOHTTPHandler.h"
+
 #include <Poco/Net/HTTPBasicCredentials.h>
 #include <Poco/Net/HTTPServerRequest.h>
 #include <Poco/Net/HTTPServerResponse.h>
-
 #include <common/logger_useful.h>
-
 #include <Common/HTMLForm.h>
 #include <Common/setThreadName.h>
 #include <Compression/CompressedWriteBuffer.h>
 #include <IO/ReadBufferFromIStream.h>
 #include <IO/WriteBufferFromHTTPServerResponse.h>
 #include <Interpreters/InterserverIOHandler.h>
-
-#include "InterserverIOHTTPHandler.h"
+#include "IServer.h"
 
 namespace DB
 {
@@ -50,7 +49,7 @@ std::pair<String, bool> InterserverIOHTTPHandler::checkAuthentication(Poco::Net:
     return {"", true};
 }
 
-void InterserverIOHTTPHandler::processQuery(Poco::Net::HTTPServerRequest & request, Poco::Net::HTTPServerResponse & response)
+void InterserverIOHTTPHandler::processQuery(Poco::Net::HTTPServerRequest & request, Poco::Net::HTTPServerResponse & response, Output & used_output)
 {
     HTMLForm params(request);
 
@@ -61,24 +60,17 @@ void InterserverIOHTTPHandler::processQuery(Poco::Net::HTTPServerRequest & reque
 
     ReadBufferFromIStream body(request.stream());
 
-    const auto & config = server.config();
-    unsigned keep_alive_timeout = config.getUInt("keep_alive_timeout", 10);
-
-    WriteBufferFromHTTPServerResponse out(request, response, keep_alive_timeout);
-
     auto endpoint = server.context().getInterserverIOHandler().getEndpoint(endpoint_name);
 
     if (compress)
     {
-        CompressedWriteBuffer compressed_out(out);
+        CompressedWriteBuffer compressed_out(*used_output.out.get());
         endpoint->processQuery(params, body, compressed_out, response);
     }
     else
     {
-        endpoint->processQuery(params, body, out, response);
+        endpoint->processQuery(params, body, *used_output.out.get(), response);
     }
-
-    out.finalize();
 }
 
 
@@ -90,30 +82,30 @@ void InterserverIOHTTPHandler::handleRequest(Poco::Net::HTTPServerRequest & requ
     if (request.getVersion() == Poco::Net::HTTPServerRequest::HTTP_1_1)
         response.setChunkedTransferEncoding(true);
 
+    Output used_output;
+    const auto & config = server.config();
+    unsigned keep_alive_timeout = config.getUInt("keep_alive_timeout", 10);
+    used_output.out = std::make_shared<WriteBufferFromHTTPServerResponse>(request, response, keep_alive_timeout);
+
     try
     {
-        if (auto [msg, success] = checkAuthentication(request); success)
+        if (auto [message, success] = checkAuthentication(request); success)
         {
-            processQuery(request, response);
+            processQuery(request, response, used_output);
             LOG_INFO(log, "Done processing query");
         }
         else
         {
             response.setStatusAndReason(Poco::Net::HTTPServerResponse::HTTP_UNAUTHORIZED);
             if (!response.sent())
-                response.send() << msg << std::endl;
+                writeString(message, *used_output.out);
             LOG_WARNING(log, "Query processing failed request: '" << request.getURI() << "' authentification failed");
         }
     }
     catch (Exception & e)
     {
-
         if (e.code() == ErrorCodes::TOO_MANY_SIMULTANEOUS_QUERIES)
-        {
-            if (!response.sent())
-                response.send();
             return;
-        }
 
         response.setStatusAndReason(Poco::Net::HTTPResponse::HTTP_INTERNAL_SERVER_ERROR);
 
@@ -122,7 +114,7 @@ void InterserverIOHTTPHandler::handleRequest(Poco::Net::HTTPServerRequest & requ
 
         std::string message = getCurrentExceptionMessage(is_real_error);
         if (!response.sent())
-            response.send() << message << std::endl;
+            writeString(message, *used_output.out);
 
         if (is_real_error)
             LOG_ERROR(log, message);
@@ -134,7 +126,8 @@ void InterserverIOHTTPHandler::handleRequest(Poco::Net::HTTPServerRequest & requ
         response.setStatusAndReason(Poco::Net::HTTPResponse::HTTP_INTERNAL_SERVER_ERROR);
         std::string message = getCurrentExceptionMessage(false);
         if (!response.sent())
-            response.send() << message << std::endl;
+            writeString(message, *used_output.out);
+
         LOG_ERROR(log, message);
     }
 }
diff --git a/dbms/programs/server/InterserverIOHTTPHandler.h b/dbms/programs/server/InterserverIOHTTPHandler.h
index fbaf432d4f9..8dc1962664c 100644
--- a/dbms/programs/server/InterserverIOHTTPHandler.h
+++ b/dbms/programs/server/InterserverIOHTTPHandler.h
@@ -1,12 +1,10 @@
 #pragma once
 
+#include <memory>
 #include <Poco/Logger.h>
 #include <Poco/Net/HTTPRequestHandler.h>
-
 #include <Common/CurrentMetrics.h>
 
-#include "IServer.h"
-
 
 namespace CurrentMetrics
 {
@@ -16,6 +14,9 @@ namespace CurrentMetrics
 namespace DB
 {
 
+class IServer;
+class WriteBufferFromHTTPServerResponse;
+
 class InterserverIOHTTPHandler : public Poco::Net::HTTPRequestHandler
 {
 public:
@@ -28,12 +29,17 @@ public:
     void handleRequest(Poco::Net::HTTPServerRequest & request, Poco::Net::HTTPServerResponse & response) override;
 
 private:
+    struct Output
+    {
+        std::shared_ptr<WriteBufferFromHTTPServerResponse> out;
+    };
+
     IServer & server;
     Poco::Logger * log;
 
     CurrentMetrics::Increment metric_increment{CurrentMetrics::InterserverConnection};
 
-    void processQuery(Poco::Net::HTTPServerRequest & request, Poco::Net::HTTPServerResponse & response);
+    void processQuery(Poco::Net::HTTPServerRequest & request, Poco::Net::HTTPServerResponse & response, Output & used_output);
 
     std::pair<String, bool> checkAuthentication(Poco::Net::HTTPServerRequest & request) const;
 };
diff --git a/dbms/tests/queries/0_stateless/00942_dataparts_500.reference b/dbms/tests/queries/0_stateless/00942_dataparts_500.reference
new file mode 100644
index 00000000000..e6a7bd76965
--- /dev/null
+++ b/dbms/tests/queries/0_stateless/00942_dataparts_500.reference
@@ -0,0 +1 @@
+< HTTP/1.1 500 Internal Server Error
diff --git a/dbms/tests/queries/0_stateless/00942_dataparts_500.sh b/dbms/tests/queries/0_stateless/00942_dataparts_500.sh
new file mode 100755
index 00000000000..cccd1b8695d
--- /dev/null
+++ b/dbms/tests/queries/0_stateless/00942_dataparts_500.sh
@@ -0,0 +1,8 @@
+#!/usr/bin/env bash
+
+# Test fix for issue #5066
+
+CURDIR=$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)
+. $CURDIR/../shell_config.sh
+
+${CLICKHOUSE_CURL} -vvv "${CLICKHOUSE_URL_INTERSERVER}?endpoint=DataPartsExchange%3A%2Fclickhouse%2Ftables%2F01-01%2Fvisits%2Freplicas%2Fsome.server.com&part=0&compress=false" 2>&1 | grep -F "< HTTP/1.1 500 Internal Server Error"
diff --git a/dbms/tests/queries/shell_config.sh b/dbms/tests/queries/shell_config.sh
index af222fc9531..7126a99b348 100644
--- a/dbms/tests/queries/shell_config.sh
+++ b/dbms/tests/queries/shell_config.sh
@@ -41,6 +41,10 @@ export CLICKHOUSE_PORT_HTTP_PROTO=${CLICKHOUSE_PORT_HTTP_PROTO:="http"}
 export CLICKHOUSE_URL=${CLICKHOUSE_URL:="${CLICKHOUSE_PORT_HTTP_PROTO}://${CLICKHOUSE_HOST}:${CLICKHOUSE_PORT_HTTP}/"}
 export CLICKHOUSE_URL_HTTPS=${CLICKHOUSE_URL_HTTPS:="https://${CLICKHOUSE_HOST}:${CLICKHOUSE_PORT_HTTPS}/"}
 export CLICKHOUSE_URL_PARAMS=${CLICKHOUSE_URL_PARAMS:="${CLICKHOUSE_URL}?database=${CLICKHOUSE_DATABASE}"}
+export CLICKHOUSE_PORT_INTERSERVER=${CLICKHOUSE_PORT_INTERSERVER:=`${CLICKHOUSE_EXTRACT_CONFIG} --try --key=interserver_http_port 2>/dev/null`} 2>/dev/null
+export CLICKHOUSE_PORT_INTERSERVER=${CLICKHOUSE_PORT_INTERSERVER:="9009"}
+export CLICKHOUSE_URL_INTERSERVER=${CLICKHOUSE_URL_INTERSERVER:="${CLICKHOUSE_PORT_HTTP_PROTO}://${CLICKHOUSE_HOST}:${CLICKHOUSE_PORT_INTERSERVER}/"}
+
 export CLICKHOUSE_CURL_COMMAND=${CLICKHOUSE_CURL_COMMAND:="curl"}
 export CLICKHOUSE_CURL=${CLICKHOUSE_CURL:="${CLICKHOUSE_CURL_COMMAND} --max-time 10"}
 export CLICKHOUSE_TMP=${CLICKHOUSE_TMP:="."}