LinkedIn confirms hacking incident

Social networking website LinkedIn has confirmed a number of accounts may have been compromised in an apparent cyber attack amid reports that up to 6.5 million passwords may have been leaked online.

In a blog post this evening, a company spokesman said: “We can confirm that some of the passwords that were compromised correspond to LinkedIn accounts.”

According to a report on the technology website ZDNet, while some of the log-in details allegedly stolen are likely to be encrypted, some information may be compromised and LinkedIn members are advised to change their passwords.

A file containing 6,458,020 encoded passwords was reportedly posted online over the past few days.

LinkedIn said it was continuing to investigate the incident.

However, it said members that have accounts associated with the compromised passwords would notice that their LinkedIn account password is no longer valid.

“These members will also receive an email from LinkedIn with instructions on how to reset their passwords,” it said.

IT security and data protection firm Sophos earlier said the leaked encrypted data did not include associated email addresses but warned that hackers will be working to crack the “unsalted” password hashes and “it is reasonable to assume that such information may be in the hands of the criminals”.

Graham Cluley, senior technology consultant at Sophos, said: “It would seem sensible to suggest to all LinkedIn users that they change their passwords as soon as possible as a precautionary step.

“Of course, make sure that the password you use is unique — in other words, not used on any other websites — and that it is hard to crack.

“If you were using the same passwords on other websites, make sure to change them too. And never again use the same password on multiple websites.”

LinkedIn, which has its international headquarters in Dublin, claims 161 million members in over 200 countries.

The site was started in the living room of co-founder Reid Hoffman in 2002 and went live the following year.

The company employs some 2,447 employees including over 100 here in Ireland.

Additional reporting: PA