The hidden dangers of unsecured IoT sensors

Why IoT devices are attractive to attackers

Attackers aren’t necessarily looking for the “crown jewels” straight away. Instead, they often go for the weakest link, and in IoT deployments, that usually means edge devices like sensors, cameras, or controllers.

• Distributed and exposed: IoT sensors are deployed in public or remote areas - EV chargers on city streets, monitoring stations in fields, logistics trackers in transit. Physical and network exposure makes them inherently harder to protect.

• Lightweight and overlooked: Unlike servers or corporate IT, many IoT devices run lightweight software stacks with limited security features. They’re built for efficiency, not resilience.

• Sheer scale: By 2030, over 40 billion connected devices are expected worldwide. That’s billions of potential entry points for attackers.

The result? One vulnerable sensor can give adversaries a foothold into entire systems.

Common attack vectors for unsecured IoT

Recent years have shown just how creative attackers can be:

• Rogue base stations: Using low-cost equipment, criminals can impersonate legitimate mobile towers, tricking IoT devices into connecting and exposing unencrypted data.

• SIM swap & identity theft: Attackers manipulate credentials or provisioning systems to hijack a device’s identity, gaining access to private systems or sensitive data flows.

• OTA hijacks: Over-the-air firmware updates — meant to keep devices secure — can themselves be hijacked if not properly authenticated, letting attackers push malicious code.

• Botnet recruitment: Insecure IoT devices are prime candidates for botnets, which can be weaponised for large-scale DDoS attacks.

These are not future risks. They are live threats affecting industries from utilities to logistics.

The business impact of unsecured sensors

The fallout from a compromised IoT device goes far beyond the device itself:

• Operational disruption: A disabled pump sensor, compromised traffic light, or jammed EV charger can halt critical services. Downtime in these cases isn’t measured in hours - it’s in public safety and lost millions.

• Data breaches: Once inside, attackers can pivot to steal customer data, payment details, or proprietary information. Verizon reports that one in three breaches already involves IoT devices.

• Reputational damage: A hacked sensor may sound minor, but the ripple effect on public trust - especially in smart cities or critical infrastructure - is enormous.

• Regulatory fines: Under frameworks like GDPR and NIS2, operators can face multi-million-euro penalties if insecure devices lead to data loss or service outages.

Why traditional defences aren’t enough

Relying on public mobile networks, generic SIM cards, or bolt-on VPNs isn’t sufficient anymore. These measures create blind spots: you don’t control how traffic is routed, you can’t prevent lateral movement between devices, and you lack visibility when something goes wrong.

The security model needs to shift — from “trust but verify” to “never trust, always verify.”

Securing IoT at the source

The answer lies in rethinking IoT security from the ground up. That starts with the SIM. By embedding Zero Trust principles directly into connectivity, every device is validated, every connection encrypted, and every request checked against policy. No assumptions, no open doors.

It’s not about patching over weaknesses — it’s about building resilience into the very fabric of your IoT network.

Download our guide
to learn about Zero Trust security for your IoT deployment.