It wasn't a glitch, some posh motherfucker with 38,000+ Eth from a few years ago dumped it from his wallet into GDX I believe it was, and, well, only 12k buy ordered were in place, sooooo
Nobody picked it up who didn't have an auto-buy though, it lasted too short and everything crashed.
Imagine if i was sitting there looking at the screen on coinbase and sudden realised it had dropped and bought a few hundred eths! I wouldn't be here!