From LeakedSource:
Twitter credentials are being traded in the tens of millions on the dark web. LeakedSource has obtained and added a copy of this data to its ever-growing searchable repository of leaked data. This data set was provided to us by a user who goes by the alias “[email protected]”, and has given us permission to name them in this blog.
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You may search for yourself in the leaked Twitter.com credentials by visiting our homepage. If your personal information appears in our copy of the Twitter credentials, or in any other leaked database that we possess, you may remove yourself for free
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This data set contains 32,888,300 records. Each record may contain an email address, a username, sometimes a second email and a visible password. We have very strong evidence that Twitter was not hacked, rather the consumer was. These credentials however are real and valid. Out of 15 users we asked, all 15 verified their passwords.
The explanation for this is that tens of millions of people have become infected by malware, and the malware sent every saved username and password from browsers like Chrome and Firefox back to the hackers from all websites including Twitter.
You can search for your info on LeakedSource’s home page, here. Read more on LeakedSource’s blog post about Twitter, here.