Scenario: "Taipei": Come a-knocking

Level: Easy

Type: Hack

Tags: hack  

Access: Email

Description: There is a web server on port :80 protected with Port Knocking. Find the one "knock" needed (sending a SYN to a single port, not a sequence) so you can curl localhost.

Root (sudo) Access: False

Test: Executing curl localhost returns a message (with md5sum ca3fd7603194ed3cec023b74b6039b15 if it has no endline char and with md5sum fe474f8e1c29e9f412ed3b726369ab65 if it does).

The "Check My Solution" button runs the script /home/admin/agent/check.sh, which you can see and execute.

Time to Solve: 15 minutes.