More than 10,000 British nationals have been approached by fake LinkedIn profiles that are associated with hostile states, according to MI5.
The UK's security organisation believes that any users that accepted such a request might have been tricked into sharing secrets.
A campaign has been launched by the Centre for the Protection of National Infrastructure (CPNI) called Think Before You Link, which warns that foreign agents are targeting officials with access to sensitive information. The project shares concerns that once a request has been accepted, the victim's colleagues will be more likely to accept a follow-up request as it looks like they share a mutual acquaintance.
Nearly all government departments and some key industries are thought to have been targeted by fake LinkedIn accounts. A large number of those approached might have engaged with the profiles that contacted them, which may have offered speaking or business and travel opportunities as ways to extract confidential information.
LinkedIn said it "welcomed" the efforts of the CPNI and its Think Before You Link campaign.
"We actively seek out signs of state-sponsored activity on the platform and quickly take action against bad actors in order to protect our members," the company said in a statement. "Our Threat Intelligence team removes fake accounts using information we uncover and intelligence from a variety of sources, including government agencies."
While the number of profiles targeting UK officials is alarming, cyber attacks are almost always less sophisticated than people imagine, according to Idax CEO Mark Rodbert.
"Technology is the most common vector, rather than the method, and cyber vulnerability often has more to do with mind-reading acts than complex technological tools," Rodbert told IT Pro.
"Cyber criminals and foreign agents draw heavily from the confidence tricksters of the past, so their methods are often quite straightforward. If you ask someone for their data, you would be surprised at how often they tell you. People make mistakes"
