It is possible to, given a global CSRF token such as the one present in the authenticity_token meta tag, forge a per-form CSRF token for any action for that session.
Given the ability to extract the global CSRF token, an attacker would be able to construct a per-form CSRF token for that session.
This is a low-severity security issue. As such, no workaround is necessarily until such time as the application can be upgraded.