firewall-rules

Challenge Text

Liar, Liar, Rules on Fire! A network administrator configured a device's firewall, but made a few errors along the way. Some of your favorite applications may have been denied... We can't worry about that yet, first step is to make sure external hosts aren't able to exploit vulnerable firewall rules.
Sum the vunerable ports and put the answer in the flag format: jctf{INSERT NUMBER}

Hint

Sometimes Google searches lead to numbers!
Focus on remote access.

Solution

Pull up list of TCP and UDP port numbers: https://en.wikipedia.org/wiki/List_of_TCP_and_UDP_port_numbers
Query through each firewall rule and note that the allowed insecure ports that provide remote access or unencrypted connection are: 513 (rlogin), 23 (telnet), 3389 (RDP)
513 + 23 + 3389 = jctf{3925}

Credit

Developed by Logan