Nostalrius Begins - Quality wow vanilla realm (1.12)

It seems like this might be a false positive with the anti-cheat engine or something else?

The addon is SellJunk, and it's technically outdated for this version of WoW. That being said it seems odd that using it to sell all grey items at once triggers a disconnect.

Thanks for the feedback!

It's likely just throttling to help server performance. Get the LazyPig addon, when you go to a vendor hold shift, it'll auto vendor at a reasonable speed.