‘Largest social media breach ever:’ Data of 200 mn X users leaked in 34 GB file: Report

In what comes as potentially the largest social media breach ever, data of some 200 million X users may have been compromised and made available on a hacking forum. The alleged breach was first reported by Safetydetective.com, whose researchers found a 34 GB downloadable file on hacking forum “BreachForums” posted by a user ‘ThinkingOne’.

The 34 GB file allegedly had data of about 201 million X users. According to Safetydetective.com, ThinkingOne claims to have shared the data after the realisation that neither X nor public and X users were aware of the ‘data breach’. ThinkingOne also claims to have “tried contacting X via several methods with no response.”

‘Data of X users genuine’

Meanwhile, researchers at Safetydetective.com claimed the data available in the file was genuine, which they verified by matching the information with their original X IDs.

“We reviewed the information corresponding to 100 users in the list, and we found that it matched what was shown on Twitter. We also verified a considerable amount of emails, which turned out to be valid email addresses, though we cannot confirm that the emails belong to the accounts listed,” the researchers said.

They further said that the alleged compromised data contained information such as X screen names and user IDs, full names, locations, email addresses, follower counts, profile data, time zones, profile images, and more.

‘Largest social media breach ever’

ThinkingOne, in a conversation with Forbes, said they were not hackers but ‘data enthusiasts” who don’t indulge in illegal acts and “ensure everything they do is legal”.

As per ThinkingOne, “This is by far the largest social media breach ever, in terms of a number of users, and there is at least a possibility that the person responsible for the breach has other data, including emails, phone numbers and passwords.”

Origin of data breach still unclear

The exact origin of the data breach is still unclear. However, ThinkingOne claims they accessed X data leaked in January 2022 and combined it with another breach leaked in January 2025.

“The dataset leaked in January 2025 included over 2.8 billion unique Twitter IDs and screennames,” ThinkingOne was quoted as saying by Forbes, “I checked a representative sample of 100 and 92 had the correct user ID and screenname.’

The hacker added: “How could someone enumerate all Twitter user IDs, unless they were an employee or this was a very serious hacking job?”