LONDON - A Russian hacker is claiming to have uploaded almost 6.5 million LinkedIn passwords.
LinkedIn in says in a tweet that "Our team is currently looking into reports of stolen passwords. Stay tuned for more."
In its posting, The Verge, a technology-focused news publication, says the hacker claims to have uploaded 6,458,020 passwords.
The Verge says the claim was made by the unidentified hacker in a Russian forum.
"It's not clear if they managed to download the usernames, but it's likely that both have been downloaded," The Verge reports. "There is a possibility that this could be a hoax, but several people have said on Twitter that they found their real LinkedIn passwords as hashes on the list. Many of the hashes include 'linkedin,' which seems to add credence to the claims."
Naked Security, a blog from Sophos, reports that a file containing some of the hacked data has been posted on the Internet, and that hackers are working together to crack them.
Graham Cluley, a security expert with Sophos, said Wednesday that investigations by Sophos researchers have confirmed that the file does contain, in part, LinkedIn passwords.
Cluley recommended LinkedIn users change their passwords "as soon as possible."
LinkedIn did not respond to repeated requests for comment but the company posted a tweet saying that its team is "looking into reports of stolen passwords."
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