Researchers at Leuven University (KU Leuven) have discovered the existence of millions of poorly secured so-called ‘tunnelling hosts’. Tunnelling hosts are servers or computers that act as intermediaries to connect computer networks. A total of more than four million vulnerable tunnelling hosts were found.
Is says nothing about what they actually found, just a bunch of hosts forwarding GRE traffic. No details on what platforms, if a bug report or CVE was filed, nothing at all.