We present two widespread design flaws in VPN client. These can be abused to make a victim leak traffic in plaintext outside the protected VPN tunnel.
Tests indicate that every VPN product is vulnerable on at least one device, the researchers say. VPNs for iPhones, iPads, MacBooks, and macOS are extremely likely to be vulnerable, that a majority of VPNs on Windows and Linux are vulnerable, and that Android is the most secure with roughly one-quarter of VPN apps being vulnerable.