Last year, Twitter exposed more than five million phone numbers and email addresses following a massive data breach. The research team of 9TO5Mac has been provided with evidence that suggests the same security vulnerability was exploited by multiple threat actors at the same time. Additionally, several sources have advertised the availability of the hacked data on the dark web for sale as well. 

This vulnerability was first reported back in January by HackerOne. Using this tool, anyone could enter a phone number or e-mail address and then find the Twitter account associated with that number or email address. A Twitter handle can be easily converted into an internal identifier used by Twitter, even though it is an internal identifier utilized by Twitter. 

In reality, a threat actor would be able to construct a single database that would contain Twitter handles, email addresses, and phone numbers accumulated from the web. 

When Twitter released an announcement in May, it confirmed that the vulnerability existed and had been patched, but it did not mention that anyone had exploited it. 

According to the restoration privacy report, a hacker had indeed used the vulnerability to gain access to millions of accounts around the world. He had gotten access to personal information as a result. 

In a Twitter thread yesterday, there was a suggestion that some threat actors had accessed the same personal data in more than one way. Having seen evidence of multiple breaches, 9to5Mac can now verify that this is indeed the case. 

The security researchers explained that, in a previous report, they had seen a dataset that contained the same information in a different format, and the source told researchers that it was "definitely a different threat actor." This was just one of several files that they had seen. The researchers at 9TO5Mac found that the dataset was just one of several similar files. 

The majority of the data is based on Twitter users in the UK, most EU member countries, and several US states. 

Essentially, the setting the security researchers are referring to here refers to a setting that is quite deeply buried within the settings of Twitter. This setting appears to be on by default if you open Twitter's settings. 

An estimated 500k record was downloaded within one hour by the bad actors, it has been reported. On the dark web, multiple sources have offered this data for sale for a price between $5,000 and $10,000. 

It has been reported that a security expert's account has been suspended after tweeting about it. There was also another security specialist whose Twitter account was suspended the same day. Chad Loder, a well-recognized computer security expert, predicted Twitter's reaction within minutes of it being announced and it was confirmed by other experts. 

There is evidence that multiple hackers have obtained the same data and combined it with other data sourced from other breaches to steal the information.