diff --git a/adm/config_form.php b/adm/config_form.php
index 28ab4217f..44f9296b6 100644
--- a/adm/config_form.php
+++ b/adm/config_form.php
@@ -414,6 +414,12 @@ if (!isset($config['cf_cert_use_seed'])) {
             ADD COLUMN `cf_cert_use_seed` TINYINT(4) NOT NULL DEFAULT '1' AFTER `cf_cert_kg_mid`; ";
     sql_query($sql, false);
 }
+if (!isset($config['cf_cert_kcp_enckey'])) {
+    $sql = "ALTER TABLE `{$g5['config_table']}` 
+            ADD COLUMN `cf_cert_kcp_enckey` VARCHAR(100) NOT NULL DEFAULT '' AFTER `cf_cert_kcp_cd`; ";
+    sql_query($sql, false);
+}
+
 if (!$config['cf_faq_skin']) {
     $config['cf_faq_skin'] = "basic";
 }
@@ -1066,6 +1072,13 @@ if ($config['cf_sms_use'] && $config['cf_icode_id'] && $config['cf_icode_pw']) {
                             <input type="text" name="cf_cert_kcp_cd" value="<?php echo get_sanitize_input($config['cf_cert_kcp_cd']); ?>" id="cf_cert_kcp_cd" class="frm_input" size="3"> <a href="http://sir.kr/main/service/p_cert.php" target="_blank" class="btn_frmline">NHN KCP 휴대폰 본인확인 서비스 신청페이지</a>
                         </td>
                     </tr>
+                    <tr>
+                        <th scope="row" class="cf_cert_service"><label for="cf_cert_kcp_enckey">NHN KCP 가맹점 인증키</label></th>
+                        <td class="cf_cert_service">
+                            <?php echo help('NHN_KCP 상점관리자 > 기술관리센터 > 인증센터 > 가맹점 인증키관리 에서 인증키 발급 후에 인증키 정보를 입력해 주세요.<br>입력하지 않거나 잘못 입력시 휴대폰 본인확인을 취소 하셨습니다. 라고 메시지가 나오면서 창이 닫히는 오류가 발생됩니다.') ?>
+                            <input type="text" name="cf_cert_kcp_enckey" value="<?php echo get_sanitize_input($config['cf_cert_kcp_enckey']); ?>" id="cf_cert_kcp_enckey" class="frm_input" maxlength="100" size="40"> <a href="https://partner.kcp.co.kr" target="_blank" class="btn_frmline">NHN KCP 상점관리자</a>
+                        </td>
+                    </tr>
                     <tr>
                         <th scope="row" class="cf_cert_service"><label for="cf_cert_limit">본인확인 이용제한</label></th>
                         <td class="cf_cert_service">
diff --git a/adm/config_form_update.php b/adm/config_form_update.php
index 81186b371..c3769a3e9 100644
--- a/adm/config_form_update.php
+++ b/adm/config_form_update.php
@@ -23,7 +23,7 @@ check_admin_token();
 
 $cf_social_servicelist = !empty($_POST['cf_social_servicelist']) ? implode(',', $_POST['cf_social_servicelist']) : '';
 
-$check_keys = array('cf_cert_kcb_cd', 'cf_cert_kcp_cd', 'cf_editor', 'cf_recaptcha_site_key', 'cf_recaptcha_secret_key', 'cf_naver_clientid', 'cf_naver_secret', 'cf_facebook_appid', 'cf_facebook_secret', 'cf_twitter_key', 'cf_twitter_secret', 'cf_google_clientid', 'cf_google_secret', 'cf_googl_shorturl_apikey', 'cf_kakao_rest_key', 'cf_kakao_client_secret', 'cf_kakao_js_apikey', 'cf_payco_clientid', 'cf_payco_secret', 'cf_cert_kg_cd', 'cf_cert_kg_mid');
+$check_keys = array('cf_cert_kcb_cd', 'cf_cert_kcp_cd', 'cf_cert_kcp_enckey', 'cf_editor', 'cf_recaptcha_site_key', 'cf_recaptcha_secret_key', 'cf_naver_clientid', 'cf_naver_secret', 'cf_facebook_appid', 'cf_facebook_secret', 'cf_twitter_key', 'cf_twitter_secret', 'cf_google_clientid', 'cf_google_secret', 'cf_googl_shorturl_apikey', 'cf_kakao_rest_key', 'cf_kakao_client_secret', 'cf_kakao_js_apikey', 'cf_payco_clientid', 'cf_payco_secret', 'cf_cert_kg_cd', 'cf_cert_kg_mid');
 
 foreach ($check_keys as $key) {
     if (isset($_POST[$key]) && $_POST[$key]) {
@@ -289,6 +289,7 @@ $sql = " update {$g5['config_table']}
                 cf_cert_kg_mid = '" . trim($_POST['cf_cert_kg_mid']) . "',
                 cf_cert_kcb_cd = '{$_POST['cf_cert_kcb_cd']}',
                 cf_cert_kcp_cd = '{$_POST['cf_cert_kcp_cd']}',
+                cf_cert_kcp_enckey = '{$_POST['cf_cert_kcp_enckey']}',
                 cf_cert_limit = '{$_POST['cf_cert_limit']}',
                 cf_cert_req = '{$_POST['cf_cert_req']}',
                 cf_sms_use = '{$_POST['cf_sms_use']}',
diff --git a/install/gnuboard5.sql b/install/gnuboard5.sql
index 2772c6f17..ddb7b99cf 100644
--- a/install/gnuboard5.sql
+++ b/install/gnuboard5.sql
@@ -295,6 +295,7 @@ CREATE TABLE IF NOT EXISTS `g5_config` (
   `cf_cert_use_seed` tinyint(4) NOT NULL DEFAULT '1',
   `cf_cert_kcb_cd` varchar(255) NOT NULL DEFAULT '',
   `cf_cert_kcp_cd` varchar(255) NOT NULL DEFAULT '',
+  `cf_cert_kcp_enckey` varchar(100) NOT NULL DEFAULT '',
   `cf_lg_mid` varchar(100) NOT NULL DEFAULT '',
   `cf_lg_mert_key` varchar(100) NOT NULL DEFAULT '',
   `cf_cert_limit` int(11) NOT NULL DEFAULT '0',
diff --git a/plugin/kcpcert/bin/ct_cli b/plugin/kcpcert/bin/ct_cli
index 2446ab62f..2a6ada0ef 100755
Binary files a/plugin/kcpcert/bin/ct_cli and b/plugin/kcpcert/bin/ct_cli differ
diff --git a/plugin/kcpcert/bin/ct_cli_exe.exe b/plugin/kcpcert/bin/ct_cli_exe.exe
index 3abbd50c0..fe5204923 100644
Binary files a/plugin/kcpcert/bin/ct_cli_exe.exe and b/plugin/kcpcert/bin/ct_cli_exe.exe differ
diff --git a/plugin/kcpcert/bin/ct_cli_x64 b/plugin/kcpcert/bin/ct_cli_x64
index 4fc53b04d..955fff043 100755
Binary files a/plugin/kcpcert/bin/ct_cli_x64 and b/plugin/kcpcert/bin/ct_cli_x64 differ
diff --git a/plugin/kcpcert/kcpcert_config.php b/plugin/kcpcert/kcpcert_config.php
index 37841e104..b715655d7 100644
--- a/plugin/kcpcert/kcpcert_config.php
+++ b/plugin/kcpcert/kcpcert_config.php
@@ -14,12 +14,15 @@ $web_siteid = '';
 if ($config['cf_cert_use'] == 2) { // 실서비스
     $site_cd = 'SM'.$config['cf_cert_kcp_cd'];
     $cert_url = 'https://cert.kcp.co.kr/kcp_cert/cert_view.jsp';
+    $kcp_enc_key = $config['cf_cert_kcp_enckey'];
 } else if ($config['cf_cert_use'] == 1) { // 테스트사용
     $site_cd = 'S6186';
     $cert_url = 'https://testcert.kcp.co.kr/kcp_cert/cert_view.jsp';
+    $kcp_enc_key = 'E66DCEB95BFBD45DF9DFAEEBCB092B5DC2EB3BF0';
 } else { // 사용안함
     $site_cd = '';
     $cert_url = '';
+    $kcp_enc_key = '';
 }
 
 if(!$site_cd)
diff --git a/plugin/kcpcert/kcpcert_form.php b/plugin/kcpcert/kcpcert_form.php
index 400c0e3a5..b82329651 100644
--- a/plugin/kcpcert/kcpcert_form.php
+++ b/plugin/kcpcert/kcpcert_form.php
@@ -27,6 +27,8 @@ if(!$ordr_idxx)
 $ct_cert = new C_CT_CLI;
 $ct_cert->mf_clear();
 
+$sbParam = '';
+
 $year          = "00";
 $month         = "00";
 $day           = "00";
@@ -47,7 +49,7 @@ $hash_data = $site_cd   .
              $sex_code  .
              $local_code;
 
-$up_hash = $ct_cert->make_hash_data( $home_dir, $hash_data );
+$up_hash = $ct_cert->make_hash_data( $home_dir, $kcp_enc_key, $hash_data );
 
 $ct_cert->mf_clear();
 ?>
@@ -88,6 +90,9 @@ $ct_cert->mf_clear();
 <!-- cert_enc_use 필수 (고정값 : 메뉴얼 참고) -->
 <input type="hidden" name="cert_enc_use" value="Y"/>
 
+<!-- 리턴 암호화 고도화 -->
+<input type="hidden" name="cert_enc_use_ext" value="Y"/>
+
 <?php if(is_mobile()) { ?>
 <!-- cert_able_yn input 비활성화 설정 -->
 <input type="hidden" name="cert_able_yn" value=""/>
@@ -101,10 +106,15 @@ $ct_cert->mf_clear();
 <!-- up_hash 검증 을 위한 필드 -->
 <input type="hidden" name="veri_up_hash" value=""/>
 
+<!-- web_siteid 을 위한 필드 -->
+<input type="hidden" name="web_siteid_hashYN" value=""/>
+
 <!-- 가맹점 사용 필드 (인증완료시 리턴)-->
 <input type="hidden" name="param_opt_1"  value="opt1"/>
 <input type="hidden" name="param_opt_2"  value="opt2"/>
 <input type="hidden" name="param_opt_3"  value="opt3"/>
+
+<input type='hidden' name='kcp_cert_lib_ver' value="<?php echo $ct_cert->get_kcp_lib_ver( $home_dir ); ?>"/>
 </form>
 
 <script>
diff --git a/plugin/kcpcert/kcpcert_result.php b/plugin/kcpcert/kcpcert_result.php
index 20828257c..06c261814 100644
--- a/plugin/kcpcert/kcpcert_result.php
+++ b/plugin/kcpcert/kcpcert_result.php
@@ -12,6 +12,7 @@ $enc_data      = "";
 $req_tx        = "";
 
 $enc_cert_data = "";
+$enc_cert_data2 = "";
 $cert_info     = "";
 
 $tran_cd       = "";
@@ -67,6 +68,11 @@ for($i=0; $i<count($key); $i++)
     {
         $enc_cert_data = f_get_parm_str ( $valParam );
     }
+    
+    if ( $nmParam == "enc_cert_data2" )
+    {
+        $enc_cert_data2 = f_get_parm_str ( $valParam );
+    }
 
     if ( $nmParam == "dn_hash" )
     {
@@ -98,7 +104,7 @@ if( $cert_enc_use == "Y" )
         // 해당 데이터의 위변조를 방지합니다
          $veri_str = $site_cd.$ordr_idxx.$cert_no; // 사이트 코드 + 주문번호 + 인증거래번호
 
-        if ( $ct_cert->check_valid_hash ( $home_dir , $dn_hash , $veri_str ) != "1" )
+        if ( $ct_cert->check_valid_hash ( $home_dir , $kcp_enc_key, $dn_hash , $veri_str ) != "1" )
         {
             if(strtoupper(substr(PHP_OS, 0, 3)) !== 'WIN') {
                 // 검증 실패시 처리 영역
@@ -122,7 +128,7 @@ if( $cert_enc_use == "Y" )
         // site_cd 와 cert_no 를 가지고 복화화 하는 함수 입니다.
         // 정상적으로 복호화 된경우에만 인증데이터를 가져올수 있습니다.
         $opt = "1" ; // 복호화 인코딩 옵션 ( UTF - 8 사용시 "1" )
-        $ct_cert->decrypt_enc_cert( $home_dir , $site_cd , $cert_no , $enc_cert_data , $opt );
+        $ct_cert->decrypt_enc_cert( $home_dir , $kcp_enc_key, $site_cd , $cert_no , $enc_cert_data2 , $opt );
 
         $comm_id        = $ct_cert->mf_get_key_value("comm_id"    );                // 이동통신사 코드
         $phone_no       = $ct_cert->mf_get_key_value("phone_no"   );                // 전화번호
diff --git a/plugin/kcpcert/lib/ct_cli_lib.php b/plugin/kcpcert/lib/ct_cli_lib.php
index ffd54d3ca..a1eb8cb8c 100644
--- a/plugin/kcpcert/lib/ct_cli_lib.php
+++ b/plugin/kcpcert/lib/ct_cli_lib.php
@@ -20,7 +20,7 @@ class   C_CT_CLI
     }
 
     // hash 처리 영역
-    function make_hash_data( $home_dir , $str )
+    function make_hash_data( $home_dir , $key , $str )
     {
         if(strtoupper(substr(PHP_OS, 0, 3)) !== 'WIN') {
             if(PHP_INT_MAX == 2147483647) // 32-bit
@@ -32,6 +32,7 @@ class   C_CT_CLI
         }
         $hash_data = $this -> mf_exec( $bin_exe ,
                                        "lf_CT_CLI__make_hash_data",
+                                       $key,
                                        $str
                                      );
 
@@ -41,7 +42,7 @@ class   C_CT_CLI
     }
 
     // dn_hash 체크 함수
-    function check_valid_hash ($home_dir , $hash_data , $str )
+    function check_valid_hash ($home_dir , $key , $hash_data , $str )
     {
         if(strtoupper(substr(PHP_OS, 0, 3)) !== 'WIN') {
             if(PHP_INT_MAX == 2147483647) // 32-bit
@@ -53,6 +54,7 @@ class   C_CT_CLI
         }
         $ret_val = $this -> mf_exec( $bin_exe ,
                                      "lf_CT_CLI__check_valid_hash" ,
+                                     $key,
                                      $hash_data ,
                                      $str
                                     );
@@ -63,7 +65,7 @@ class   C_CT_CLI
     }
 
     // 암호화 인증데이터 복호화
-    function decrypt_enc_cert ( $home_dir, $site_cd , $cert_no , $enc_cert_data , $opt)
+    function decrypt_enc_cert ( $home_dir, $key , $site_cd , $cert_no , $enc_cert_data , $opt)
     {
         if(strtoupper(substr(PHP_OS, 0, 3)) !== 'WIN') {
             if(PHP_INT_MAX == 2147483647) // 32-bit
@@ -73,6 +75,7 @@ class   C_CT_CLI
 
             $dec_data = $this -> mf_exec( $bin_exe ,
                                          "lf_CT_CLI__decrypt_enc_cert" ,
+                                          $key,
                                           $site_cd ,
                                           $cert_no ,
                                           $enc_cert_data ,
@@ -84,6 +87,7 @@ class   C_CT_CLI
 
             $dec_data = $this -> mf_exec( $bin_exe ,
                                          "lf_CT_CLI__decrypt_enc_cert" ,
+                                          $key,
                                           $site_cd ,
                                           $cert_no ,
                                           $enc_cert_data
@@ -96,6 +100,26 @@ class   C_CT_CLI
         parse_str( str_replace( chr( 31 ), "&", $dec_data ), $this->m_dec_data );
     }
 
+    function get_kcp_lib_ver( $home_dir )
+    {
+        if(strtoupper(substr(PHP_OS, 0, 3)) !== 'WIN') {
+            if(PHP_INT_MAX == 2147483647) // 32-bit
+                $bin_exe = $home_dir . '/bin/ct_cli';
+            else
+                $bin_exe = $home_dir . '/bin/ct_cli_x64';
+        } else {
+            $bin_exe = $home_dir . '/bin/ct_cli_exe.exe';
+        }
+        
+        $ver_data = $this -> mf_exec( $bin_exe , 
+                                       "lf_CT_CLI__get_kcp_lib_ver"
+                                     );
+
+        if ( $ver_data == "" ) { $ver_data = "HS04"; }
+        
+        return $ver_data;
+    }
+    
     // 인증데이터 get data
     function mf_get_key_value( $name )
     {