Earlier this month, security researcher Troy Hunt identified the first tranche of that mega-dump, named Collection #1 by its anonymous creator, a set of cobbled-together breached databases Hunt said represented 773 million unique usernames and passwords. Now other researchers have obtained and analyzed an additional vast database called Collections #2–5, which amounts to 845 gigabytes of stolen data and 25 billion records in all. After accounting for duplicates, analysts at the Hasso Plattner Institute in Potsdam, Germany, found that the total haul represents close to three times the Collection #1 batch.
“This is the biggest collection of breaches we’ve ever seen,” says Chris Rouland, a cybersecurity researcher and founder of the IoT security firm Phosphorus.io, who pulled Collections #1–5 in recent days from torrented files. He says the collection has already circulated widely among the hacker underground: He could see that the tracker file he downloaded was being “seeded” by more than 130 people who possessed the data dump, and that it had already been downloaded more than 1,000 times. “It’s an unprecedented amount of information and credentials that will eventually get out into the public domain,” Rouland says.