Changes made to LinkedIn's privacy policy means web users will find their names and photos used in advertising on the business social network, warns Sophos.

According to the security firm, the changes to the policy included an "on-by-default" feature and while LinkedIn did place a notification on its website of the changes, many web users may have overlooked the affect the changes will have.

The change reads: "LinkedIn may sometimes pair an advertiser's message with social content from LinkedIn's network in order to make the ad more relevant. When LinkedIn members recommend people and services, follow companies, or take other actions, their name/photo may show up in related ads shown to you. Conversely, when you take these actions on LinkedIn, your name/photo may show up in related ads shown to LinkedIn members."

Graham Cluley, senior technology consultant at Sophos, revealed many LinkedIn users have complained about the changes.

"Unfortunately this is just the latest example of a social network introducing sensitive new policies without giving users the chance to say first whether they want to opt-in," said Cluley.

"We're used to this from Facebook, and it's disappointing to see LinkedIn follow in their footsteps. This feature certainly wasn't available when many of LinkedIn's users first signed up for the service, and as the majority of people don't tend to check privacy settings after they've set up an account, many people won't even be aware that their image and name could be used in this fashion."

Sophos said LinkedIn users should access their account settings and disable 'Manage Sscial advertising' to opt-out of the changes.

According to Catalin Cosoi, head of the Online Threats Lab at Bitdefender, a social network's most valuable assets are users and their information.

"With this in mind, we can reasonably expect that, at some point, new features that deliberately or accidentally expose users' data to other parties outside of their network (either other users or advertisers) might be rolled-out. Most services have even taken legal provisions and stipulate in their Terms of Service that they can freely access and "associate" your content with your picture and name."

"Generally speaking, there is little to be done in order to avoid these privacy invasions. The big question is whether social networks could do more to help users understand when changes are made and what the implications are. We advise social networking users to carefully control the information they publish on such websites in order to minimise the impact of such leaks."

LinkedIn said the privacy and trust of its members is central to what the social network does and it strives to remain true to the commitment of providing members with consistent, clear and easy-to-use controls for their LinkedIn account settings.

"In early June, we announced on the LinkedIn company blog, planned changes to our privacy policy ahead of a small test of new social ads which would enable members to see which companies, products and services are recommended by their network, so helping them make better business decisions. In the post, we also explained how members could opt-out of the new ad format and not share their recommendations with their network," the social network said.

The social network said it then followed up with a second blog post explaining the new social ads in more detail and reminding members of the ability to opt-out.

"In addition, as LinkedIn does with all changes to its User Agreement and Privacy Policy, we notified our members of the changes to these documents via a banner displayed to when they logged in to their account. This banner contained a link to the new documents, including a summary of the changes and links from which our members could easily access their account setting," LinkedIn said.

"We strive to be consistent in how we communicate with our members and help them stay up to date and in control of their data as we continue to innovate new ways to make them more productive and successful.'