jones_supa writes "A user in a Russian forum is claiming to have hacked LinkedIn to the tune of almost 6.5 million account details. The user uploaded 6,458,020 SHA-1 hashed passwords, but no usernames. Several people have said on Twitter that they found their real LinkedIn passwords as hashes on the list. The Verge spoke with Mikko Hyppönen, Chief Research Officer at F-Secure, who thinks this is a real collection. He told us he is 'guessing it's some sort of exploit on their web interface, but there's no way to know.' We will have to wait for LinkedIn to report back to be sure what exactly has happened." An anonymous reader tipped us to related news: The LinkedIn iOS application harvests information from your calendar and transmits it to their servers unencrypted.