I was playing on a single player world without lan on and I decided to use one of my mods commands. I loved that command so much I spammed it and then I got kicked from my own singleplayer world. I tried this on vanilla minecraft and it did the same. It gave me a minecraft kick exception node saying "disconnect.spam" and then I hit back to title screen and it took me to the server list.
Duplicate of MC-14923, please use the search function to see if your bug has already been submitted. Currently over 56% of tickets are being resolved as duplicate.