Spoilerwall is a Python script and can be downloaded from GitHub.
"Firewall? How about Fire'em'all! Stop spending thousands of dollars on big teams that you don't need! Just fire up the Spoilers Server and that's it!" the developer writes.
Such scans are something which attackers carry out to ascertain what application they should use to attack a given server.
A sample scan is provided using the Shodan search engine.
The developer adds a playful warning, "Be careful in your next CTF (capture the flag) – you never know when the spoilers are coming!"