https://consumerist.com/2017/10/03/verizon-now-says-that-all-yahoo-accounts-were-probably-compromised-by-massive-hack/

Last year, Yahoo revealed that some 1.5 billion accounts — representing about 1 billion users — had been compromised by a data breach going back years. Now that Yahoo’s new parent company Verizon has had a chance to investigate it turns out that the number of accounts compromised by the hack was… well, every single one of them.

Verizon disclosed the results of its internal investigation into the breach, which began in Aug. 2013, this afternoon in a filing [PDF] with the Securities and Exchange Commission.