FTP Enumeration
Nmap scripts
ls -al /usr/share/nmap/scripts/ | grep ftp-*
Metasploit modules
search type:auxiliary name:ftp
use auxiliary/scanner/ftp/ftp_version
use auxiliary/scanner/ftp/ftp_login
Hydra bruteforce
hydra -L /usr/share/metasploit-framework/data/wordlists/common_users.txt -P /usr/share/metasploit-framework/data/wordlists/unix_passwords.txt 10.10.23.24 -t 4 ftp
FTP Passive Mode fix
On anonymous login use ls -lsa to see hidden files. If passive mode hangs:
ncftp -u anonymous -p anonymous 10.10.110.100
set passive off
ls