LFI to RCE 취약점 수정

adm/contentformupdate.php

@@ -18,6 +18,18 @@ check_admin_token();
 if ($co_himg_del)  @unlink(G5_DATA_PATH."/content/{$co_id}_h");
 if ($co_timg_del)  @unlink(G5_DATA_PATH."/content/{$co_id}_t");
 
+$error_msg = '';
+
+if( $co_include_head && ! is_include_path_check($co_include_head) ){
+    $co_include_head = '';
+    $error_msg = '/data/file/ 또는 /data/editor/ 포함된 문자를 상단 파일 경로에 포함시킬수 없습니다.';
+}
+
+if( $co_include_tail && ! is_include_path_check($co_include_tail) ){
+    $co_include_tail = '';
+    $error_msg = '/data/file/ 또는 /data/editor/ 포함된 문자를 하단 파일 경로에 포함시킬수 없습니다.';
+}
+
 $sql_common = " co_include_head     = '$co_include_head',
                 co_include_tail     = '$co_include_tail',
                 co_html             = '$co_html',
@@ -74,7 +86,11 @@ if ($w == "" || $w == "u")
         @chmod($dest_path, G5_FILE_PERMISSION);
     }
 
-    goto_url("./contentform.php?w=u&co_id=$co_id");
+    if( $error_msg ){
+        alert($error_msg, "./contentform.php?w=u&co_id=$co_id");
+    } else {
+        goto_url("./contentform.php?w=u&co_id=$co_id");
+    }
 }
 else
 {

adm/qa_config_update.php

@@ -8,6 +8,18 @@ auth_check($auth[$sub_menu], 'w');
 
 check_admin_token();
 
+$error_msg = '';
+
+if( $qa_include_head && ! is_include_path_check($qa_include_head) ){
+    $qa_include_head = '';
+    $error_msg = '/data/file/ 또는 /data/editor/ 포함된 문자를 상단 파일 경로에 포함시킬수 없습니다.';
+}
+
+if( $qa_include_tail && ! is_include_path_check($qa_include_tail) ){
+    $qa_include_tail = '';
+    $error_msg = '/data/file/ 또는 /data/editor/ 포함된 문자를 하단 파일 경로에 포함시킬수 없습니다.';
+}
+
 $sql = " update {$g5['qa_config_table']}
             set qa_title                = '{$_POST['qa_title']}',
                 qa_category             = '{$_POST['qa_category']}',
@@ -29,8 +41,8 @@ $sql = " update {$g5['qa_config_table']}
                 qa_image_width          = '{$_POST['qa_image_width']}',
                 qa_upload_size          = '{$_POST['qa_upload_size']}',
                 qa_insert_content       = '{$_POST['qa_insert_content']}',
-                qa_include_head         = '{$_POST['qa_include_head']}',
-                qa_include_tail         = '{$_POST['qa_include_tail']}',
+                qa_include_head         = '{$qa_include_head}',
+                qa_include_tail         = '{$qa_include_tail}',
                 qa_content_head         = '{$_POST['qa_content_head']}',
                 qa_content_tail         = '{$_POST['qa_content_tail']}',
                 qa_mobile_content_head  = '{$_POST['qa_mobile_content_head']}',
@@ -47,5 +59,9 @@ $sql = " update {$g5['qa_config_table']}
                 qa_5                    = '{$_POST['qa_5']}' ";
 sql_query($sql);
 
-goto_url('./qa_config.php');
+if($error_msg){
+    alert($error_msg, './qa_config.php');
+} else {
+    goto_url('./qa_config.php');
+}
 ?>

bbs/content.php

@@ -19,7 +19,7 @@ if (!$co['co_id'])
 
 $g5['title'] = $co['co_subject'];
 
-if ($co['co_include_head'])
+if (is_include_path_check($co['co_include_head']))
     @include_once($co['co_include_head']);
 else
     include_once('./_head.php');
@@ -85,7 +85,7 @@ if(is_file($skin_file)) {
     echo '<p>'.str_replace(G5_PATH.'/', '', $skin_file).'이 존재하지 않습니다.</p>';
 }
 
-if ($co['co_include_tail'])
+if (is_include_path_check($co['co_include_tail']))
     @include_once($co['co_include_tail']);
 else
     include_once('./_tail.php');

bbs/qahead.php

@@ -9,7 +9,7 @@ if (G5_IS_MOBILE) {
     include_once('./_head.php');
     echo conv_content($qaconfig['qa_mobile_content_head'], 1);
 } else {
-    if($qaconfig['qa_include_head'])
+    if(is_include_path_check($qaconfig['qa_include_head']))
         @include ($qaconfig['qa_include_head']);
     else
         include ('./_head.php');

bbs/qatail.php

@@ -7,7 +7,7 @@ if (G5_IS_MOBILE) {
     include_once('./_tail.php');
 } else {
     echo conv_content($qaconfig['qa_content_tail'], 1);
-    if($qaconfig['qa_include_tail'])
+    if(is_include_path_check($qaconfig['qa_include_tail']))
         @include ($qaconfig['qa_include_tail']);
     else
         include ('./_tail.php');

lib/common.lib.php

@@ -3259,4 +3259,13 @@ function check_write_token($bo_table)
 
     return true;
 }
+
+// include 하는 경로에 data file 경로가 포함되어 있는지 체크합니다.
+function is_include_path_check($path='')
+{
+    if( !$path || preg_match('/\/data\/(file|editor)\/[A-Za-z0-9_]{1,20}\//', $path) ){
+        return false;
+    }
+    return true;
+}
 ?>

lib/thumbnail.lib.php

@@ -273,8 +273,8 @@ function thumbnail($filename, $source_path, $target_path, $thumb_width, $thumb_h
             }
         }
     } else if ($size[2] == 3) {
-        $src = imagecreatefrompng($source_file);
-        imagealphablending($src, true);
+        $src = @imagecreatefrompng($source_file);
+        @imagealphablending($src, true);
     } else {
         return;
     }