Skip to Main Content
September 30, 2021

They’re Watching You! Protecting Yourself From Hidden Cameras

Written by Paul Koblitz
Hardware Security Assessment Organizational Training Penetration Testing Physical Security Security Testing & Analysis Technical Counter Surveillance Measures

Hidden cameras, spy cameras, nanny cams—whatever you call them, you are under surveillance much more than you may realize. While outdoor perimeter cameras and doorbell cameras are commonplace and have been used for quite some time to monitor property, other nefarious hidden cameras are popping up all over the place.

Generally, any camera placed inside of a dwelling is usually not for monitoring purposes. There should be no reason for cameras to be placed in or around bathrooms, bedrooms, or any other changing area. However, cameras have been found in homes, Airbnbs, hotels, VBRO bookings, and other places that people can stay while traveling as a means to invade personal privacy.

Where should you look for hidden cameras?

Cameras need three (3) things to be effective: a line of sight to what it is monitoring; reliable power; and either a network connection or internal device storage. Because of that, cameras are usually hidden in places that can conceal the device and any necessary wiring. These include:

  • Lamps
  • Power adapters
  • Outlet/light switch covers
  • Smoke detectors
  • Thermostats
  • Vents
  • Telephones
  • Alarm clocks
  • TV and TV-related items (DVD, video game consoles, etc.)
  • Other stationary furniture items (desks, mirrors, picture frames, etc.)

Detecting surveillance devices with your own device...your phone!

In the past, organizations or VIPs would hire a security professional to do Technical Surveillance Countermeasures (TSCM), also known as a “bug” or electronic surveillance sweep using specialty tools and/or by physically locating the device visually through close, time-consuming inspection. Today, we all have a very powerful device in our pockets.

Using a mobile phone is one of the best ways to detect hidden cameras because all the tools to do a preliminary sweep are at your fingertips, and most people have phones with them constantly. Cell phones can help in two (2) ways—assisting in visual detection or finding the device on the local network. Here are some simple ways to get started.

  1. Visual Detection
  • With every sweep, it is best to have the room as dark as possible. Turn off all of the lights, close all the curtains, pull blackout shades if they are available. From there, you can use your flashlight on your phone and slowly scan the room looking for things that are reflecting light that seem strange. If you notice something, turn on the lights and investigate it further. This method is not suitable for detecting cameras in mirrors, however.
  • Many cameras will use infrared (IR) for recording in the dark as well as a traditional camera. This is another great advantage of a phone, as it can detect IR where your eyes cannot. To test this method, take a standard IR TV remote control, point it at your camera lens, and then hit any button on the remote. You should see one or several pink/red lights that you cannot see with the naked eye while looking at the remote. You may also need to use the selfie cam because many rear-facing cameras have IR filters now. Thus, whichever camera works for seeing the TV remote IR lights will also detect IR from hidden cameras. Again, with the room as dark as possible, scan the room slowly with your camera and see if it picks up any red lights.

2. Network Detection

  • For network detection, first join your cell phone to the wireless network. Several network monitoring tools do a good job of illuminating what is on the network and give you an idea of what they are doing. The most prominent tools that I use on my phone are available on both iOS and Android. These are: 
  • Fing – This excellent network scanner shows what is connected to the network and what IP address they have. It will also give some basic information to help identify the devices like the manufacturer (Apple, Samsung, Microsoft, LG, etc.). While not always possible, Fing will also show the type of connected device (printer, computer, iPad, router, etc.).
  • HE Network Tools – This suite of tools delivers most of the network diagnostics a Network Engineer would use. For network detection, HE provides a great port scanning tool that will allow you to dig a little deeper into the nature of the device. Specifically, doing a Transmission Control Protocol (TCP) port scan on a suspected IP address will tell you all of the ports that are open. Typical ports for cameras are 80, 8080, 443, and 8443. Because all web ports will likely have a web page associated with it, you can browse to the associated web page (http://192.168.10.215:8080 as an example) to get a sense of what that web page is and potentially see if an IP camera is using it. Additionally, other ports to look for are 1935, 5234, and 554.

Taking the next step in your detection capability

There are several tools available to help you find hidden spying devices, and it’s easy to perform your own research to find the one that is best for your specific use. There are many styles from independent manufacturers that can be purchased online. Amazon is one of the better places to start researching devices as the customer reviews will let you know if the device will do what you want. Just typing a search string for “anti-spy bug detectors” will start you on your way to some great information. There are many all-in-one options that will detect IR, Radio Frequency (RF), Global Positioning System (GPS), and magnetics. One of the great things is they are also easy to travel with. For my personal uses, I have one device that is specifically geared to detect each source that I want to find—but that is not necessarily traveler-friendly.

What should you do if you find a hidden camera?

It can be disconcerting when finding a hidden camera in a private place. My suggestions if you find a secret monitoring device are:

  • Do not touch the device if possible.

You may alert the person who put it there and leave your own fingerprints on it.

  • Leave the dwelling.

Again, it is best not to alert someone who may be watching or listening to you, giving them time to prepare for what they’re going to do next.

  • Contact the hotel headquarters or the booking agency.

Obviously, if it’s an Airbnb private home or the local hotel manager, they may be the one who put it there. The central management can take action and investigate whether the person should be banned from the service or fired.

  • Consider calling the authorities.

In some places and some instances, it may be warranted to contact local law enforcement. It’s important to consider whether you will want to press charges if the perpetrator is found or potentially have your video shown in court.

Protecting yourself from hidden cameras can save you the embarrassment of someone intruding into your private activities. Sophisticated devices and tools can be employed depending on your interest and desired capability. With a few simple steps from visual detection to using your mobile phone’s tools and available applications, you can discover when you may be watched without your consent.