TFTP (69)
TFTP is also known as Trivial File Transfer Protocol which runs on port number 69. TFTP protocol does not need any authentication like is used in FTP (anonymous:any_password). TFTP does not perform error detection regarding file sharing. This is because TFTP works on UDP. Thus, TFTP is faster than FTP. TFTP often used for transferring files such as audios, videos and images.
Enumeration
TFTP nmap scan
sudo nmap -n -Pn -sU -oN tftp.txt -p 69 -sV --script tftp-enum $IP
Some versions of tftp are run interactively
tftp 192.168.0.101
tftp> get myfile.txt
We can try to obtain a shell
tftp 191.168.0.101 <<< "get shell5555.php shell5555.php"