How to replace div classes/sections in Wordpress

Question

How do you replace certain page codes when your CMS is Wordpress?

To be specific, I need to change a footer section of a page that has the following code: <ul class="menu social_media">. I need to change the code to <ul class="menu social_media2">.

But for some reason I can't find the section where I can edit this HTML code. I have FTP access but the numerous folders are so overwhelming. Where do I look? I have a feeling that I should be looking for the specific template used for the page but I really can't locate any.

This is one of the pages that has the code which I need to change: http://www.criminal-lawyers.com.au/courts/character-reference. You will see that there's a positioning error with the social media icons at the footer. I can edit the CSS file but the same code applies to the site's homepage and if I edit the CSS file, it will solve the positioning error on this page but will cause issues with the footer of the homepage. Hence I need to change the code.

---

As requested by a commenter below, here's the code of the footer.php file that I found in one of our FTP folders:

<?php
/**
 * @package WordPress
 * @subpackage Theme_Compat
 * @deprecated 3.0
 *
 * This file is here for Backwards compatibility with old themes and will be removed in a future version
 *
 */
_deprecated_file( sprintf( __( 'Theme without %1$s' ), basename(__FILE__) ), '3.0', null, sprintf( __('Please include a %1$s template in your theme.'), basename(__FILE__) ) );
?>

<hr />
<div id="footer" role="contentinfo">
<!-- If you'd like to support WordPress, having the "powered by" link somewhere on your blog is the best way; it's our only promotion or advertising. -->
    <p>
        <?php printf(__('%1$s is proudly powered by %2$s'), get_bloginfo('name'),
        '<a href="http://wordpress.org/">WordPress</a>'); ?>
        <br /><?php printf(__('%1$s and %2$s.'), '<a href="' . get_bloginfo('rss2_url') . '">' . __('Entries (RSS)') . '</a>', '<a href="' . get_bloginfo('comments_rss2_url') . '">' . __('Comments (RSS)') . '</a>'); ?>
        <!-- <?php printf(__('%d queries. %s seconds.'), get_num_queries(), timer_stop(0, 3)); ?> -->
    </p>
</div>
</div>

<!-- Gorgeous design by Michael Heilemann - http://binarybonsai.com/kubrick/ -->
<?php /* "Just what do you think you're doing Dave?" */ ?>

        <?php wp_footer(); ?>
</body>
</html>