Internet TCP port 9100 is commonly used by printers for receiving print jobs over a network. This port is associated with the Raw Print Service, which allows data to be sent directly to a printer without being formatted by a print driver. Examples of software that use this port include Microsoft Windows' built-in print services and HP JetDirect card. It's also used by some 3D printers and CNC machines for remote job submission.
TCP port 9100 is commonly used for network printing and has been exploited in the past by hackers. They have used this port to gain unauthorized access to network printers, often causing them to print endless streams of gibberish, wasting paper and ink. In some cases, hackers have also been able to use this port to gain access to the network the printer is connected to, potentially compromising sensitive data. Additionally, hackers have exploited this port to launch Denial of Service (DoS) attacks, disrupting network services. In more sophisticated attacks, hackers have used this port to install malware or execute arbitrary code, turning the printer into a launching pad for further attacks.
