Dust attack or something else?

A while back I got a new ledger and it came with a $30 BTC voucher, which I ended up claiming and it was the only Bitcoin transaction I had done on it.

Today I noticed another transaction, for almost an identical amount. When I checked the fee, they paid $165 to send me $30.

Looking at the transaction, a total of 5.2 BTC was sent to over 350 addresses.

I’d expect a dust attack to be spending less resources than 300k. It’s just crazy to me, I guess it works so stay safe out there, always triple check your addresses, use whitelists and address books.

Transaction: f8a5e4d3722736a98519755a23df7e248e111980e203afcfb15ead5f9cbb200a