The developers of the Dark Souls game series have announced the disabling of the multiplayer feature for versions on personal computers. The reason for this decision was a recently discovered exploit that allowed third parties to gain access to players' PCs.
The vulnerability was that, by going into network mode, a hacker could run almost any code on another user's computer. In fact, in this way he could do anything with the system, and the owner of the PC could not oppose anything. Therefore, FromSoftware suggested that it would be better for now to limit the fans of their creativity from intrusions in order to remove the risks of critical damage to computers.
It is assumed that the console versions of Dark Souls are not affected by this exploit.