diff --git a/src/web/server/.htaccess b/src/web/server/.htaccess
new file mode 100644
index 0000000..cc6a67b
--- /dev/null
+++ b/src/web/server/.htaccess
@@ -0,0 +1,28 @@
+# SQL Injection 방어 - Apache 레벨 WAF
+# Time-based Blind SQL Injection 공격 패턴 차단
+
+<IfModule mod_rewrite.c>
+    RewriteEngine On
+
+    # SLEEP(), BENCHMARK() 등 시간 지연 함수 차단 (Time-based Blind SQLi 핵심 패턴)
+    RewriteCond %{QUERY_STRING} (sleep|benchmark|waitfor\s+delay|pg_sleep) [NC]
+    RewriteRule .* - [F,L]
+
+    RewriteCond %{REQUEST_URI} (sleep|benchmark|waitfor\s+delay|pg_sleep) [NC]
+    RewriteRule .* - [F,L]
+
+    # POST body의 SQLi 패턴은 mod_security로 처리 (아래 참조)
+</IfModule>
+
+# PHP 에러 메시지 노출 방지
+<IfModule mod_php7.c>
+    php_flag display_errors Off
+    php_flag log_errors On
+</IfModule>
+<IfModule mod_php.c>
+    php_flag display_errors Off
+    php_flag log_errors On
+</IfModule>
+
+# 서버 정보 숨기기
+ServerSignature Off
diff --git a/src/web/server/record/update_result_record.php b/src/web/server/record/update_result_record.php
index 79f110d..22140a1 100644
--- a/src/web/server/record/update_result_record.php
+++ b/src/web/server/record/update_result_record.php
@@ -16,21 +16,16 @@ $prev_best_record_id = -1;
 $prev_best_record = 0;
 
 $prev_best_record_id = get_best_record($maestro_id, $app_id, $player_id);
-echo "id : ".$prev_best_record_id." ".$prev_best_record;
 
 if($prev_best_record_id === null || $prev_best_record_id < 0) {
-	echo "insert";
 	insert_best_record($maestro_id, $app_id, $player_id, $record);
 } else {
-	echo $record." ".$prev_best_record;
 	if(is_highest_record_prefer_app($app_id)) {
 		if($record > $prev_best_record) {
-			echo "update";
 			update_best_record($prev_best_record_id, $record);
 		}
 	} else {
 		if($record < $prev_best_record) {
-			echo "update";
 			update_best_record($prev_best_record_id, $record);
 		}
 	}
@@ -38,9 +33,6 @@ if($prev_best_record_id === null || $prev_best_record_id < 0) {
 
 // highest record is the highest record
 $app_highest_record = get_app_highest_record($maestro_id, $app_id, $player_id);
-echo "\napp_highest_record : $app_highest_record";
-
-// echo "\nrecord : $record";
 if($app_highest_record == null) {
 	insert_app_highest_record($maestro_id, $app_id, $player_id, $record);
 	// echo "\ninsert_app_highest_record : $record";
diff --git a/src/web/server/setup/connect_db.php b/src/web/server/setup/connect_db.php
index b0e98f6..e7763e7 100644
--- a/src/web/server/setup/connect_db.php
+++ b/src/web/server/setup/connect_db.php
@@ -15,7 +15,7 @@ if($hasServiceDBSetting == true) {
 // connect db
 $db_conn = new mysqli($db_host, $db_user, $db_passwd, $db_name);
 if ($db_conn->connect_error) {
-    set_error_message("Failed to connect DB: ".$db_conn->connect_error);
+    set_error_message("DB connection failed.");
     send_result_fail();
     exit;
 } else {