A massive Twitter data breach disclosed a few months ago appears to be bigger than initially reported.
In August, Twitter admitted that a vulnerability affecting its systems had been exploited to obtain user data. The issue, introduced in June 2021, could have been exploited to determine whether a specified phone number or email address was tied to an existing Twitter account, even for accounts where the information should have been private.
The vulnerability was reported to the social media giant in January and it was quickly fixed, but not before it was exploited by malicious actors.
Twitter confirmed exploitation of the flaw in August 2022, after reports started circulating that the weakness had been leveraged to collect data on 5.4 million users. This database was being offered for sale at the time on hacking forums for $30,000.
Cybersecurity expert Chad Loder reported on Twitter last week that he had been informed of a massive Twitter data breach. Loder obtained a database containing phone numbers, account names, account bios, and verified status.
The researcher said the accounts included ones belonging to celebrities, politicians and government agencies. The exposed accounts had phone numbers associated with countries in the European Union, as well as the United States.
Loder initially believed that the data was not related to the breach disclosed in August, but further analysis revealed that multiple threat groups likely exploited the same vulnerability to obtain data. This would explain why there are multiple databases of roughly the same type of data but in different formats and sizes.
Twitter could not be reached for comment, but the company appears to be aware of the situation as it suspended Loder’s account shortly after he announced obtaining the data.
It appears that one threat actor exploited the vulnerability to obtain information on 5.4 million Twitter accounts, but others obtained even more records.
Loder said on Mastodon that there appear to be tens of millions of impacted accounts, “perhaps over 100 million”.
A few days before Loder announced a potentially new breach at Twitter, the previously announced database of 5.4 million accounts was made available on a popular hacker forum for free. The poster said they are aware of an additional 1.4 million records associated with suspended accounts. The leaked database stores usernames, display names, profile descriptions, locations, email addresses, and phone numbers.
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