GHSA-w542-cpp9-r3g7 Field Test CSRF vulnerability

• RubyGems field_test: >= 0.2.0, < 0.4.0 → fixed in 0.4.0

The Field Test dashboard is vulnerable to cross-site request forgery (CSRF) with non-session based authentication methods in versions v0.2.0 through v0.3.2. Impact The Field Test dashboard is vulnerable to CSRF with non-session based authentication methods, like basic authentication. Session-based authentication methods (like Devise's default authentication) are not affected. A CSRF attack works by getting an authorized user to visit a malicious website and then performing requests on behalf of the user. In this instance, a single endpoint is affected, which allows for changing the variant assigned to a user. All users running an affected release should upgrade immediately. Technical Details Field Test uses the `protect_from_forgery` method from Rails to prevent CSRF. However, this defaults to `:null_session`, which has no effect on non-session based authentication methods. This has been changed to `protect_from_forgery with: :exception`.