It has been revealed that the email addresses of LinkedIn users can easily be exposed via a web browser add-on tool.
A free brower extension for Google Chrome called Sell Hack will pop up a "hack in" button on LinkedIn profiles, once installed.
Even if they are not connected Users can then find the email address associated with the account. LinkedIn has said it was taking legal action over the plug-in and advised users to uninstall it.
Sell Hack has insisted that the the tool was created for marketing professionals and that all data is available publicly.
"We just do the heavy lifting and complicated computing to save you time, we aren't doing anything malicious to LinkedIn," the website says.
But it seems that the social network for professionals did not agree.
"We are doing everything we can to shut Sell Hack down. On 31 March LinkedIn's legal team delivered Sell Hack a cease-and-desist letter as a result of several violations," a spokesman said.
"LinkedIn members who downloaded Sell Hack should uninstall it immediately and contact Sell Hack requesting that their data be deleted."
Members should "use caution" before downloading any third-party extension or app.
"Often times, as with the Sell Hack case, extensions can upload your private LinkedIn information without your explicit consent," the spokesman added.
Are you a Linkedin user? Is this cause for concern? Tell us your thoughts in the comments below