You can send data to a specific port without needing NetCat by using the /dev/tcp
or /dev/udp
special files in Linux, depending on whether you want to use TCP or UDP for the connection.
Sending Data
The /dev/udp
and /dev/tcp
special files allow you to send data to a specific port on a local or remote machine. Here is the syntax for sending data using these special files:
echo "Hello World" > /dev/[udp|tcp]/<host>/<port>
Here are some example of sending the string “Hello World” to a local port 8888
:
# Sending data using UDP
echo "Hello World" > /dev/udp/127.0.0.1/8888
# Sending data using TCP
echo "Hello World" > /dev/tcp/127.0.0.1/8888
Explanation:
/dev/udp/
or/dev/tcp/
: These special files allow you to send data to a specific port using either UDP or TCP.<host>
: The IP address or hostname of the target machine.<port>
: The port number on the target machine.echo "Hello World"
: The message you want to transmit. This can be any string or data you want to send. (Ex.cat file.txt > /dev/udp/127.0.0.1/8888
)
This is a super useful method for quickly testing connectivity without needing to install additional tools like NetCat. Happy testing! 🙂