When I scanned a web application for open ports using built in nmap command, it showed me that there is a closed port 6969 in which a service is running named acmsoda. When I did some googling on this, I found that it is the standard port run by BitTorrent client. What is actually this service acmsoda do? Is that a security threat to open this port?
According to this link, it can be a backdoor for attackers.
Backdoor assassin trojans may open the port 6969 to listen for the attacker. These malwares may enter the system through any infected likes applications or torrents.
For security, it is important to know which process opens which port.
Run these commands to get information about processes and their ports:
sudo netstat -ltup sudo lsof -i
6969 is the default port for the most famous bittorrent tracker software.