It feels like not a week goes by without someone sending me yet another credential stuffing list. It’s usually something to the effect of “hey, have you seen the Spotify breach”, to which I politely reply with a link to my old No, Spotify Wasn’t Hacked blog post (it’s just the output of a small set of credentials successfully tested against their service), and we all move on. Occasionally though, the corpus of data is of much greater significance, most notably the Collection #1 incident of early 2019. But even then, the rapid appearance of Collections #2 through #5 (and more) quickly became, as I phrased it in that blog post, “a race to the bottom” I did not want to take further part in.
Until the Naz.API list appeared. Here’s the back story: this week I was contacted by a well-known tech company that had received a bug bounty submission based on a credential stuffing list posted to a popular hacking forum:
Image: Troy Hunt
Whilst this post dates back almost 4 months, it hadn’t come across my radar until now and inevitably, also hadn’t been sent to the aforementioned tech company. They took it seriously enough to take appropriate action against their (very sizeable) user base which gave me enough cause to investigate it further than your average cred stuffing list. Here’s what I found:
319 files totalling 104GB
70,840,771 unique email addresses
427,308 individual HIBP subscribers impacted
65.03% of addresses already in HIBP (based on a 1k random sample set)
That last number was the real kicker; when a third of the email addresses have never been seen before, that’s statistically significant.
