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IMSI Catcher Counter-Surveillance: Detecting Stingrays at Protests

Freddy Martinez

Freddy Martinez demonstrates low-cost counter-surveillance tools to detect IMSI catchers (Stingrays) and rogue cellular base stations during political protests.

Summary

The Threat of Cell-Site Simulators in Public Spaces

Law enforcement and intelligence agencies increasingly deploy IMSI catchers (Stingrays) to covertly intercept cellular traffic, track locations, and log attendee identities at protests.

How IMSI Catchers Exploit 2G/3G Protocol Flaws

Freddy Martinez explains how cell-site simulators broadcast high-power beacon signals to force phones to downgrade to unauthenticated 2G GSM protocols.

Building Open-Source IMSI Catcher Detectors

Martinez demonstrates deploying low-cost hardware—including rooted Android phones running SnoopSnitch and custom SDR monitoring nodes.

Practical Counter-Surveillance Tactics for Activists

The author provides actionable digital safety practices—including toggling airplane mode, using Faraday bags, and relying on end-to-end encrypted messaging.

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