This port is also commonly accessed by load balancing software, which helps determine the best route for traffic. IMAP servers have numerous buffer overflows that allow compromise during the login. There is also a popular Linux worm that spreads by port 143. Finger is usually used during the reconnaissance phase of an attack, because the finger service provides information about users. Fingering a user will often display the contents of the .plan file or Finger can be used to list all the users who are logged on to the system.
Attackers can use misconfigured wingate services to tunnel through a firewall into a network.
The proxy servers can be used to mask an attack or surf the web anonymously. Many attack scripts install a backdoor shell at this port, these backdoors can be utilized for better access by attackers. Trojan programs can be used to get remote access to a user's machine. Host Port Scan Laurie detected several scan directed at an individual host. The most common scan was the SYN scan, but other scans such as SYN-FIN also appeared regularly on her network.