LinkedIn users are being bombarded by spam emails after the social network was hacked and hashed passwords of users dumped online.
Members of the business network told The Register that they had received scores of invitations to "link in" with new connections, often flagged with warnings from their email provider that the missive couldn't be verified as coming from LinkedIn.com.
One user, consultant Peter Baston, told El Reg that he was receiving invitations in groups, which isn't normal, and was frustrated by the lack of advice on LinkedIn's front page.
While the network has put up two blog postings about the data breach, which saw a list of 6.5 million hashed passwords posted on a Russian Dropbox-alike, there isn't any information on its actual website.
LinkedIn admitted that at least some of the passwords on the list were genuine and told people who were affected that their old passwords would be deleted and that they'd get an email prompting them to reset.
Unfortunately some of the emails urging people to input a new password by clicking on a link have turned out to be phishes. The real LinkedIn password-reset email has no links in it.
Although many companies of at least a half decent size seem to get hacked these days, LinkedIn has come in for criticism because the passwords were only hashed and not salted, a weak encryption process.
"For eons we have reminded companies that security and connectivity are opposites and the more you move in one direction the other is affected... and when you have an enforced connectivity regardless model pushed to the master revenue plan added to antiquated security systems and zip due diligence like LinkedIn – that's a FUBAR train wreck waiting to happen," said Baston, who runs his own quality assurance consultancy.
In the same blog posting that told users about the password reset, LinkedIn said that its databases were now salted as well as hashed.
About two thirds of the hashed passwords dumped online have now been cracked, according to estimates from security biz Sophos.
Passwords alone are not enough to give hackers the chance to spew spam, meaning fears that the cyber-crims have lifted email addresses as well are well-founded. Alternatively, the hackers, or the people to whom they flogged the info, may still have access to LinkedIn's databases.
The social network for suits had not responded to a request for comment at the time of publication. ®