Internet-Security.com TCP port 2002 details

TCP 2002 is commonly used for reverse Telnet to serial port 2 on console/terminal servers.
Cisco IOS terminal servers (e.g., Cisco 2509/2511 and newer async-capable routers) map TCP ports 2001–20xx to async lines; connecting to 2002 reaches line 2 via Telnet.
The ser2net daemon on Linux often ships/example-configs mapping 2000/2001/2002 to /dev/ttyS0–ttyS2, so many deployments expose port 2 on TCP 2002 (raw or RFC2217).
Dedicated serial/console devices (e.g., Digi PortServer TS, Opengear ACM/IM, Moxa NPort) are commonly configured so that TCP 2002 provides raw/RFC2217 socket access to serial port 2.
Security note: because these services are typically cleartext Telnet or raw TCP, exposed 2002/TCP is frequently targeted for unauthorized access to attached console ports.

TCP 2002