Computerworld - In response to widespread reports of a massive data breach at LinkedIn, the company Wednesday confirmed that passwords belonging to "some" of its members have been compromised.

In a carefully worded blog post, LinkedIn director Vicente Silveira said the company has confirmed that an unspecified number of hashed passwords posted publicly on a Russian hacker forum earlier this week, "correspond to LinkedIn accounts."
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'LeakedIn' Web app checks for compromised LinkedIn passwords
It is believed millions of the LinkedIn password hashes have been cracked, putting users at risk
By Jeremy Kirk, IDG News Service
June 07, 2012 11:44 AM ET

A New York-based web developer and his colleagues have built a web-based application for people to see if their LinkedIn password hash is among 6.5 million released on a Russian hacker forum.

The password breach, revealed on Wednesday, is significant due to the detailed personal data stored by LinkedIn and the chance for hackers to spear phish high-level executives or spread malicious links.
'LeakedIn' Web app checks for compromised LinkedIn passwords