All versions of the package github.com/greenpau/caddy-security are vulnerable to Insufficient Session Expiration due to improper user session invalidation upon clicking the "Sign Out" button. User sessions remain valid even after requests are sent to /logout and /oauth2/google/logout. Attackers who gain access to an active but supposedly logged-out session can perform unauthorized actions on behalf of the user.
According to WASC, "Insufficient Session Expiration is when a web site permits an attacker to reuse old session credentials or session IDs for authorization."