Firewalls Don't Stop Dragons Podcast

Firewalls Don't Stop Dragons Podcast


TunnelVision, VPNs and You

September 30, 2024

Two security researchers showed how many modern VPN services are vulnerable to malicious misconfiguration, exposing some or all of your internet traffic. While this is not likely to impact most of us, it does expose the limitations of Virtual Private Networks and why they are not silver bullets for security of privacy – despite many marketing claims to the contrary. Today we’ll discuss how TunnelVision works, how it can be mitigated, and how this affects different privacy threat models with the two researchers from Leviathan Security, Dani Cronce and Lizzie Moratti.


Interview Notes

Further Info

Table of Contents

Use these timestamps to jump to a particular section of the show.



  • 0:01:23: Reminder: brainstorming survey
  • 0:01:47: Podcast chapter markers!
  • 0:02:54: Interview setup
  • 0:05:55: What is a VPN and what isits intended purpose?
  • 0:10:27: If most connections are secured today, why do we need a VPN?
  • 0:12:40: Why do we trust a VPN provider more than our internet access provider?
  • 0:17:40: What are you trying to do with a VPN?
  • 0:19:13: Who can see my internet traffic?
  • 0:25:30: What is TunnelVision and what are the implications for VPN users?
  • 0:29:42: What’s a less technical way to understand TunnelVision?
  • 0:33:06: Why might I not want all my traffic to go through the VPN?
  • 0:35:02: How dangerous is TunnelVision for the average person?
  • 0:42:30: How did the VPN companies respond?
  • 0:51:19: What VPN features can mitigate the risk?
  • 0:57:42: Have any VPN makers fixed this problem? Do OS vendors have responsibility here?
  • 1:02:11: Do you have recommendations for VPNs? Is there new tech that might help here?
  • 1:04:00: Would privacy regulations help here?
  • 1:06:24: What are you working on next?
  • 1:08:51: Interview wrap-up
  • 1:13:31: Looking ahead