I am trying to configure and start vsftpd 2.3.4 but I get (code=exited, status=203/EXEC)

For educational purposes, I am attempting to create a vulnerable service on an Ubuntu 20.04 server by installing vsftpd 2.3.4. Since the version is outdated, I am configuring everything manually.

1. Initially, I created the /etc/vsftp.conf file and assigned it permissions of 644 and the root property.

2. The folder vsftpd-2.3.4 containing the followers was moved to /usr/sbin/ and assigned permissions of 755 with root as the owner.

3. Finally, I edited the /etc/systemd/system/vsftpd.service file as follows:

[Unit]Description=vsftpd FTP serverAfter=network.target[Service]Type=simpleExecStart=/usr/sbin/vsftpd-2.3.4 /etc/vsftpd.confRestart=on-abort[Install]WantedBy=multi-user.target

After running the code below :sudo systemctl daemon-reloadsudo systemctl start vsftpdsudo systemctl status vsftpd

I get:enter image description here

enter image description here

Do you have any suggestions for solving the problem?