The coolest anti-surveillance tools at Defcon [video]

**TL;DR:** At Def Con, independent hackers and privacy advocates are creating affordable, open-source tools that allow ordinary people to detect and protect themselves from pervasive surveillance technologies like stingray cell towers and smart city cameras. ## The Def Con Ethos: Hacking for Privacy Def Con is one of the world's largest and oldest hacker conferences, held annually in Las Vegas since 1993. It gathers security researchers, hackers, makers, journalists, and even federal agents who share a passion for understanding how technology works. The event is both a conference and a spectacle, featuring "villages" dedicated to topics from lock-picking to car hacking, IoT to social engineering. While many attend for the competitions and talks, a crucial theme for many participants is developing tools to counter the growing but often invisible landscape of surveillance technology. This article details several such counter-surveillance tools showcased at the conference. ## Detecting Smart City Cameras: The Murmur Detector **Creator:** Kenneth Payne **Website:** kernelpanic.tech Kenneth Payne builds hardware to detect surveillance technology. One of his creations is a small device, sometimes called a "crow detector," designed to passively detect smart cameras like those from the company Axon (formerly known as Taser or "crow"). **How it works:** * It uses an ESP32 microcontroller in Wi-Fi promiscuous mode. * The device scans for the Wi-Fi probe requests emitted by smart cameras. * It specifically looks for the OUI (Organizationally Unique Identifier), which is the first six characters of a Bluetooth or MAC address that identifies the manufacturer. * When a known OUI is detected, a beeper sounds, alerting the user. * Payne notes that due to MAC address randomization, detection is becoming harder, so researchers are now looking at Bluetooth UUIDs and other protocol data. **DIY and Accessibility:** Payne emphasizes that these surveillance devices are everywhere. His tool is designed for the average person. He sells the finished device, but also offers the bare circuit boards and components for under $10, with wiring diagrams available on his website, making it accessible for hobbyists to build themselves. ## Detecting Fake Cell Towers: Ray Hunter **Creators:** Cooper Quentin (Cyber Tiger) & the Electronic Frontier Foundation (EFF) **Website:** eff.org/rayhunter Ray Hunter is an open-source software and hardware project for detecting IMSI-catchers, also known as "stingrays" or fake cell towers. These are portable devices used by law enforcement, criminals, or spies to mimic a real cell tower, tricking nearby phones into connecting to them. This allows them to identify users (via their IMSI), track their location, and potentially intercept calls and text messages. **How it works:** * Ray Hunter is software that runs on inexpensive, readily available mobile hotspot devices (costing $20-$40 from eBay or Amazon). * The software analyzes the control traffic between your phone's modem and cell towers. * It looks for telltale signal characteristics and fingerprints of a fake base station device. * A green light on the device indicates normal operation; a red light signifies suspicious activity has been detected. * Users can then download a Pcap (packet capture) file to further analyze the network traffic in tools like Wireshark or send it to the EFF team for analysis. **Goal:** The project aims to demystify how these attacks work in the U.S. and create a tool that is cheap, easy to use, and accessible to everyone, not just security experts. ## Drive Scanning and Tracking Detection: Biscuit Ultra **Developer:** Hedge **Search term:** "Biscuit Ultra" or "Biscuit Pro" The Biscuit Ultra is a multi-function drive-scanning device highlighted at Def Con. It is designed to help users map and understand the surveillance infrastructure around them. **Key Features:** * **Scanning:** It scans for Wi-Fi, Bluetooth devices, and smart cameras (specifically Axon security cameras). * **Drive Mapping:** It logs all discoverable devices and can map the locations of smart cameras during a drive. * **Tracking Alerts:** If the device detects the same tracking device (like an AirTag or similar tracker) multiple times within a specific interval, it alerts the user that they might be being followed. Data is saved to an SD card for analysis. * **Probe Sniffing:** It can also sniff out Wi-Fi probe requests, showing what networks a device (like your phone) has previously connected to and is broadcasting. ## Off-Grid Communication: Meshtastic **Device shown:** LilyGo T-Deck **Software:** Meshtastic For communication that doesn't rely on the internet or cellular networks, hackers are using Meshtastic software on LoRa devices. * **How it works:** Meshtastic is an open-source, off-grid, mesh network system. In the U.S., it operates on the 915MHz frequency. * **Functionality:** Messages are transmitted from node to node across the mesh. A user can control it via a paired smartphone app or directly on a device like the T-Deck, which has a small keyboard and screen. * **Use Case:** It's useful for private group communication during events like Def Con, where cellular networks can be congested, or for any situation where internet connectivity is unavailable or undesirable. ## The Bigger Picture: Community-Driven Protection The overarching message from Def Con is that the tools to protect privacy and understand technology are not coming from large corporations or governments. They are being built by a dedicated community of hackers and hobbyists, often with limited budgets and in their spare time. Examples include: * **The $20 hotspot** running Ray Hunter to detect fake cell towers. * **The $10 ESP32 board** that beeps when you drive past a smart camera. * **A pager-sized device** that warns you if you are being tracked by a single vehicle for too long. The consensus is clear: surveillance technology is pervasive, but it is not invisible to those who know how to look. These tools democratize the ability to detect and understand it, empowering more people to protect their digital privacy. Source: [https://www.youtube.com/watch?v=-2uAsJ5EPAw](https://www.youtube.com/watch?v=-2uAsJ5EPAw)