Blog: How Tos

The snooping girl on a train, again. How to compromise a business

Jo Dalton 02 Dec 2019


So, I’m on a train, again, sat at a four-seat table, next to two men facing each other. From their conversation and interactions I’ve concluded that they are colleagues.

The chap to my left is clearly working on implementation plans for a building management system, for a company I know (yeah, I get around).

Private conversation?

From their chatter, phone calls, and an easily readable laptop screen, I knew:

  • their onsite meetings schedule
  • one serious issue was to do with an internet connected pressure valve
  • the site, building, and floor which was affected
  • a bunch of contact names and email addresses
  • who was free to be on site, and who had to be escorted

I had good mobile connectivity so I Googled him and his organisation. I couldn’t see the other guy’s device but LinkedIn helped me work out that it was the CTO.

From there I did a quick check to look for available devices with their Wi-Fi turned on. Using my iPhone I checked for available Airdrop users, and Yes, “Dave’s iPhone” was visible and available (not his real name BTW).

Within an hour I had collated enough information for me to develop a physical Social Engineering plan, and with what they’d leaked I reckon I could have drawn up a plan of attack against the building management system.

If I had malicious intent I could easily have taken it further, but that’s not me so I settled in to a security podcast instead.

Should I have spoken up?

I really wanted to say something, to make them aware that they were haemorrhaging sensitive and useful information in public. But where would I start? More to the point there was no guessing how they’d react. I would have felt like a serious stalker and having such a critical discussion on a train didn’t seem like the greatest idea.

Let’s go back to what I’d seen and heard. I knew that the company they were working with and talking about had a robust ISMS and was accredited up to the hilt. What was glaringly apparent was how little impact / influence that had on their supply chain. No amount of security policy and process could erase what I’d heard.

So, what have we learned?

Summary and Quick Tips

  • Think about whether you really need to work in a public place. Why not read or simply enjoy the peace?
  • If you do need to work in public get a privacy filter for your laptop screen
  • Don’t trust strangers. I’ve said it once and I’ll say it again, you never know who you are sat with
  • Use caution on untrusted networks – use a VPN if you must connect, or use mobile data
  • Deny / ignore any Bluetooth connection requests
  • For Mac & iOS users; turn Airdrop off. See
  • Don’t use untrusted charging ports / devices. If you have to charge, use  a USB data blocker
  • Try to pre-book seats that are tucked away in a corner to minimise exposure, or arrange a workspace that can provide privacy
  • If you must make calls on a train, be careful what you discuss; I could be listening

Last, but by no means least

Communicate all of the above to your colleagues, especially senior staff.

Set clear expectations and ensure everyone is aware of these risks and how you expect them to be managed.

Do you know what your colleagues or contractors are doing with your information on the train, or in the pub for that matter?