Nostalrius Begins - Quality wow vanilla realm (1.12)

From my experience on retail if you got caught using this exploit it resulted in a warning from GM. So it's relevant to assume that in case of consecutive violation you would end up at least temporary banned.
But many things on Nostalrius ToU-wise differ from retail and if they ever wanted to fix it, this would have been fixed already.
And there are more important "fixes" to be done, like unkitable Stitches and making you undrownable in Moonglade.