To run
edit /etc/hosts and add 127.0.0.1 somerandomsite.bla
To run the webserver cd webserver/ ./rebuild.sh
This starts the webserver on port 8081.
To start up on of the vulnerable services. cd into spring-cloud-v1-vuln or spring-boot-hello-world-feature-enum and run mvn clean spring-boot:run which will build and run the vulnerable service This requires Java 8. It may work with newer Java versions, but not tested.
Then open a web browser at http://somerandomsite.bla:8081 Then select the link which matches the vulnerable service currently running. The shutdown payload works with both services.