If you use the /scon or /scid commands in certain ways, and don't manage the incoming text properly, users could make your mIRC perform any command, including running the DOS format command to format your c: drive. It is up to the user to prevent these things from happening.
Here is a sample that would be used to have a bot msg a channel on another network:
UNSAFE:
/scon 2 msg #chan $1-
---------------
SAFE:
/scon 2
/msg #chan $1-
/scon -r
-genius_at_work
