In what appears to be yet another privacy blow to Twitter, a hacker is now selling data allegedly from 400+ million Twitter users.
In a post published on the ‘Breached’ forum yesterday, the hacker explained that the data was acquired in 2021 and early 2022. This timeframe lines up with the previous Twitter data leak of 5.4 million users that we reported in July.
The hacker has confirmed the data was obtained via the same vulnerability.
As to the legitimacy of the data, everything appears to check out.
A few of the leaked “celebrities” and notable users in the sample include:
- Alexandria Ocasio-Cortez
- Kevin O’Leary
- Donald Trump Junior
- Piers Morgan
- Brian Krebs (security researcher)
Analysis and verification of data sample
The seller has listed two samples for verification on the hacker forum. One is directly in the post and contains noteworthy individuals (above). The second sample contains 1,000 users from verified Twitter accounts saved in a .CSV file.
We examined the data sample of 1,000 users that was released via a third-party file-sharing website. When cross-checking Twitter users in the sample with publicly available information, the data appears to be authentic. Some of the accounts did not have a linked phone number.
Furthermore, the hacker is also requesting to go through a middleman service via the forum’s owner Pompompurin, which further bolster’s the hacker’s claims.
How did the breach allegedly happen?
Based on statements made by the hacker, it appears this data was from the same API vulnerability as the previous breach. This vulnerability allowed the hacker to enter known email addresses and match them up to Twitter accounts. A similar type of exploit also resulted in the Facebook leak of 533 million users in 2021.
The seller is claiming that the vulnerability was exploited in 2021 and early 2022, before Twitter eventually patched it.
Looking at the Hacker One report from the previous data breach, the Twitter vulnerability was patched on January 13, 2022.
Brian Krebs, a security researcher who is also listed in the data sample for this latest breach, obtained more information from the hacker about how the leak transpired:
The seller told me they scraped the data using the same set of weaknesses in Birdsite APIs that allowed the scraping (and publishing) early this year of profile data on 5.4M Twitter users.– Brian Krebs on Mastadon
They said they scraped the data via an exploit that was patched earlier this year, in the login api, and specifically the part of it that checks for duplicate accounts.
That, according to the seller, leaked the Twitter user ID, which was then converted via another Twitter API into a username. They also said that same iterative process worked for user telephone numbers.
Should the data prove to be accurate, this would be the largest Twitter breach on record, massively dwarfing the previous breach of 5.4 million users. Twitter is already being investigated by the EU for the previous breach.
Like Meta/Facebook, who was fined $276 million for their previous data leak, this breach could result in large fines under Europe’s GDPR privacy laws.
This breach could also put millions of Twitter users at risk for fraud, phishing attacks, and more, as the seller explained in a separate post on paste.ee that has since been removed:
Restore Privacy has reached out to Twitter for comment, but we have not heard back at the time of publication.
We will update this article with any new developments.