How feasible would it to have a gem that sits in middleware that would check for possible attacks before the string gets any further and block/share IPs of peop

How feasible would it to have a gem that sits in middleware that would check for possible attacks before the string gets any further and block/share IPs of people fishing for exploits? I could see it as a service company that shares blacklist info between sites and can even find new exploits from the "bad" requests.