Novel attack against virtually all VPN apps neuters their entire purpose

Researchers have devised an attack against nearly all virtual private network applications that forces them to send and receive some or all traffic outside of the encrypted tunnel designed to protect it from snooping or tampering.

TunnelVision, as the researchers have named their attack, largely negates the entire purpose and selling point of VPNs, which is to encapsulate incoming and outgoing Internet traffic in an encrypted tunnel and to cloak the user’s IP address. The researchers believe it affects all VPN applications when they’re connected to a hostile network and that there are no ways to prevent such attacks except when the user's VPN runs on Linux or Android. They also said their attack technique may have been possible since 2002 and may already have been discovered and used in the wild since then.

The effect of TunnelVision is “the victim's traffic is now decloaked and being routed through the attacker directly,” a video demonstration explained. “The attacker can read, drop or modify the leaked traffic and the victim maintains their connection to both the VPN and the Internet.”