Need code check please!

[marcus123]

Guys I want to use this code for the login popup, it works and everything doesn't need massive jquery file. Could you please check it for security issues?

<span class="welcome" id="quick_login">{$lang->welcome_guest} <a href="#login_form" id="login_pop" class="login">{$lang->welcome_login}</a> <a href="{$mybb->settings['bburl']}/member.php?action=register" class="register">{$lang->welcome_register}</a></span>
<a href="#" class="overlay" id="login_form"></a>
<div class="popup">
<font size="4">Welcome Back!</font><br>
Type your Username and Password.
<div>
<br>
            <form method="post" action="member.php">
            <input type="hidden" name="action" value="do_login">
            <input type="hidden" name="url" value="{$mybb->settings['bburl']}/index.php">
            <input type="hidden" name="quick_login" value="1">
            <input type="text" name="quick_username" id="quick_login_username" value="Username" class="textbox" onfocus="if(this.value == 'Username') { this.value=''; }" onblur="if(this.value == '') { this.value='Username'; }">&nbsp;<br><br>
             <input type="password" name="quick_password" id="quick_login_password" value="{$lang->login_password}" class="textbox" onfocus="if(this.value == '{$lang->login_password}') { this.value=''; }" onblur="if(this.value == '') { this.value='{$lang->login_password}'; }">
            <br><br><input type="submit" name="submit" value="Log in" class="button_accedi">
<span class="remember_me">
                <input type="checkbox" name="quick_remember" id="quick_login_remember" value="yes" class="checkbox" checked="checked">
                <label for="quick_login_remember"> {$lang->remember_me}</label>
            </span>
&nbsp&nbsp&nbsp&nbsp&nbsp&nbsp

<a href="{$mybb->settings['bburl']}/member.php?action=lostpw">{$lang->lost_password}</a>&nbsp&nbsp
</form>
<a class="close" href="#close"></a>
</div>