diff --git a/app/models/application_model.rb b/app/models/application_model.rb
index 551fe482b..c3d267e5f 100644
--- a/app/models/application_model.rb
+++ b/app/models/application_model.rb
@@ -5,7 +5,7 @@ class ApplicationModel < ActiveRecord::Base
   include ApplicationModel::HasCache
   include ApplicationModel::CanLookup
   include ApplicationModel::CanLookupSearchIndexAttributes
-  include ApplicationModel::ChecksAttributeLength
+  include ApplicationModel::ChecksAttributeValuesAndLength
   include ApplicationModel::CanCleanupParam
   include ApplicationModel::HasRecentViews
   include ApplicationModel::ChecksUserColumnsFillup
diff --git a/app/models/application_model/checks_attribute_length.rb b/app/models/application_model/checks_attribute_length.rb
deleted file mode 100644
index 5254b035c..000000000
--- a/app/models/application_model/checks_attribute_length.rb
+++ /dev/null
@@ -1,39 +0,0 @@
-# Copyright (C) 2012-2016 Zammad Foundation, http://zammad-foundation.org/
-module ApplicationModel::ChecksAttributeLength
-  extend ActiveSupport::Concern
-
-  included do
-    before_create :check_attribute_length
-    before_update :check_attribute_length
-  end
-
-=begin
-
-check string/varchar size and cut them if needed
-
-=end
-
-  def check_attribute_length
-    attributes.each { |attribute|
-      next if !self[ attribute[0] ]
-      next if !self[ attribute[0] ].instance_of?(String)
-      next if self[ attribute[0] ].empty?
-      column = self.class.columns_hash[ attribute[0] ]
-      next if !column
-      limit = column.limit
-      if column && limit
-        current_length = attribute[1].to_s.length
-        if limit < current_length
-          logger.warn "WARNING: cut string because of database length #{self.class}.#{attribute[0]}(#{limit} but is #{current_length}:#{attribute[1]})"
-          self[ attribute[0] ] = attribute[1][ 0, limit ]
-        end
-      end
-
-      # strip 4 bytes utf8 chars if needed
-      if column && self[ attribute[0] ]
-        self[attribute[0]] = self[ attribute[0] ].utf8_to_3bytesutf8
-      end
-    }
-    true
-  end
-end
diff --git a/app/models/application_model/checks_attribute_values_and_length.rb b/app/models/application_model/checks_attribute_values_and_length.rb
new file mode 100644
index 000000000..27a680866
--- /dev/null
+++ b/app/models/application_model/checks_attribute_values_and_length.rb
@@ -0,0 +1,54 @@
+# Copyright (C) 2012-2016 Zammad Foundation, http://zammad-foundation.org/
+module ApplicationModel::ChecksAttributeValuesAndLength
+  extend ActiveSupport::Concern
+
+  included do
+    before_create :check_attribute_values_and_length
+    before_update :check_attribute_values_and_length
+  end
+
+=begin
+
+1) check string/varchar size and cut them if needed
+
+2) check string for null byte \u0000 and remove it
+
+=end
+
+  def check_attribute_values_and_length
+    columns = self.class.columns_hash
+    attributes.each { |name, value|
+      next if value.blank?
+      next if !value.instance_of?(String)
+      column = columns[name]
+      next if !column
+
+      # strip null byte chars (postgresql will complain about it)
+      if column.sql_type == 'text'
+        if Rails.application.config.db_null_byte == false
+          self[name].delete!("\u0000")
+        end
+      end
+
+      # for varchar check length and replace null bytes
+      limit = column.limit
+      if limit
+        current_length = value.length
+        if limit < current_length
+          logger.warn "WARNING: cut string because of database length #{self.class}.#{name}(#{limit} but is #{current_length}:#{value})"
+          self[name] = value[0, limit]
+        end
+
+        # strip null byte chars (postgresql will complain about it)
+        if Rails.application.config.db_null_byte == false
+          self[name].delete!("\u0000")
+        end
+      end
+
+      # strip 4 bytes utf8 chars if needed (mysql/mariadb will complain it)
+      next if self[name].blank?
+      self[name] = self[name].utf8_to_3bytesutf8
+    }
+    true
+  end
+end
diff --git a/config/initializers/db_preferences_mysql.rb b/config/initializers/db_preferences_mysql.rb
index 121608f10..9de0ac255 100644
--- a/config/initializers/db_preferences_mysql.rb
+++ b/config/initializers/db_preferences_mysql.rb
@@ -1,6 +1,7 @@
 # mysql
 if ActiveRecord::Base.connection_config[:adapter] == 'mysql2'
   Rails.application.config.db_4bytes_utf8 = false
+  Rails.application.config.db_null_byte = true
 
   # mysql version check
   #  mysql example: "5.7.3"
diff --git a/config/initializers/db_preferences_postgresql.rb b/config/initializers/db_preferences_postgresql.rb
index 8f72504c4..b62f7082c 100644
--- a/config/initializers/db_preferences_postgresql.rb
+++ b/config/initializers/db_preferences_postgresql.rb
@@ -2,6 +2,7 @@
 if ActiveRecord::Base.connection_config[:adapter] == 'postgresql'
   Rails.application.config.db_case_sensitive = true
   Rails.application.config.db_like = 'ILIKE'
+  Rails.application.config.db_null_byte = false
 
   # postgresql version check
   #  example output: "9.5.0"
diff --git a/lib/stats/ticket_reopen.rb b/lib/stats/ticket_reopen.rb
index 38b3afacc..360d549d4 100644
--- a/lib/stats/ticket_reopen.rb
+++ b/lib/stats/ticket_reopen.rb
@@ -66,6 +66,7 @@ class Stats::TicketReopen
   def self.log(object, o_id, changes, updated_by_id)
     return if object != 'Ticket'
     ticket = Ticket.lookup(id: o_id)
+    return if !ticket
 
     # check if close_at is already set / if not, ticket is not reopend
     return if !ticket.close_at
diff --git a/test/unit/ticket_null_byte_test.rb b/test/unit/ticket_null_byte_test.rb
new file mode 100644
index 000000000..aa3fdbd6a
--- /dev/null
+++ b/test/unit/ticket_null_byte_test.rb
@@ -0,0 +1,34 @@
+# encoding: utf-8
+require 'test_helper'
+
+class TicketNullByteTest < ActiveSupport::TestCase
+  test 'null byte test' do
+    ticket1 = Ticket.create!(
+      title: "some title \u0000 123",
+      group: Group.lookup(name: 'Users'),
+      customer_id: 2,
+      updated_by_id: 1,
+      created_by_id: 1,
+    )
+    assert(ticket1, 'ticket created')
+
+    article1 = Ticket::Article.create!(
+      ticket_id: ticket1.id,
+      from: 'some_customer_com-1@example.com',
+      to: 'some_zammad_com-1@example.com',
+      subject: "com test 1\u0000",
+      message_id: 'some@id_com_1',
+      body: "some\u0000message 123",
+      internal: false,
+      sender: Ticket::Article::Sender.find_by(name: 'Customer'),
+      type: Ticket::Article::Type.find_by(name: 'email'),
+      updated_by_id: 1,
+      created_by_id: 1,
+    )
+    assert(article1, 'ticket created')
+
+    ticket1.destroy!
+    article1.destroy!
+
+  end
+end