First of all, you don't need to specify containerPort here as there is nothing listening on any tcp port in your hping3 container:

$ kubectl exec -ti second -- /bin/sh                                                                               
/ # netstat -ntlp
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address           Foreign Address         State       PID/Program name

In fact you don't even need to provide any command as hping3 is already defined as an ENTRYPOINT in this docker image and you don't really need to overwrite it. All you need in order to run your hping3 Pod is the following yaml manifest:

apiVersion: v1
kind: Pod
metadata:
  name: second
spec:
  containers:
    - name:  hping3
      image: utkudarilmaz/hping3
      args: ["IP-address"]

Yes, providing some args is obligatory in this case, otherwise your container will fall into CrashLoopBackOff state.

As you can read in the very brief description of the image in its README.md:

Usage:

docker pull utkudarilmaz/hping3:latest
docker run utkudarilmaz/hping3:latest [parameters] target_ip

providing target_ip is obligatory, but you don't have to provide anything else.

Although the above usage description doesn't say anything about running this image on kubernetes, such short description should be totally enough for us and we should be able to translate it "from docker to kubernetes language".

Take a look at the following section, titled Define a Command and Arguments for a Container, in the official kubernetes docs, especially this fragment:

When you override the default Entrypoint and Cmd, these rules apply:

• If you do not supply command or args for a Container, the defaults defined in the Docker image are used.

• If you supply a command but no args for a Container, only the supplied command is used. The default EntryPoint and the default Cmd defined in the Docker image are ignored.

• If you supply only args for a Container, the default Entrypoint defined in the Docker image is run with the args that you supplied.
• If you supply a command and args, the default Entrypoint and the default Cmd defined in the Docker image are ignored. Your command is run with your args.

From the above we are particularly interested in the third point:

• If you supply only args for a Container, the default Entrypoint defined in the Docker image is run with the args that you supplied.

which means that in our kubernetes Pod definition we may supply only args and it's totally fine. As the ENTRYPOINT is already defined in the utkudarilmaz/hping3 image, there is no need to overwrite it by defining a command.

I was able to reproduce the error messsage you get only when trying to connect to hping3 container in CrashLoopBackOff state:

$ kubectl exec -ti second -- hping3 [IP-address]                                                                  
error: unable to upgrade connection: container not found ("hping3")

But when it runs, kubectl exec works without any issues:

$ kubectl exec -ti second -- hping3 [IP-address]
HPING [IP-address] (eth0 [IP-address]): NO FLAGS are set, 40 headers + 0 data bytes

Btw. hyphens in your command look a bit strange and they are not exactly the same characters as - and are not interpreted correctly when copied from the code snippet in your question, leading to strange errors like the following:

Error from server (NotFound): pods "–it" not found

So please mind the exact characters that you use in your commands.

As to the explanation of the error message you see when you kubectl describe your Pod:

"hping3 [IP-address]": executable file not found in $PATH: unknown

it says clearly that an executable named "hping3 IP-address" (yes, name of a single file!) cannot be found in your $PATH and I'm sure you don't have executable with such name 😉

If you provide a command this way:

command: ["hping3 [IP-address]"]

keep in mind that the whole string between the double quotes is interpreted as a single command / executable. That's why it was trying to look for executable file named "hping3 IP-address" but for obvious reasons it couldn't find it.

As already mentioned in comments, the correct usage of the command field can be:

command: ["hping3","[IP-address]"]

but in your case you don't really need it.

I hope the above explanation was helpful.