Connected Device Security Flaws: What They Are and How to Fix Them

TL;DR: Most connected device security flaws trace back to one problem: the maker cannot see what software is inside the device. Default passwords, unpatched open-source components, and insecure interfaces are the usual culprits, and they have caused real breaches from the Mirai botnet to smart-camera leaks. New rules like the EU Cyber Resilience Act now make fixing them mandatory, starting with a software bill of materials.

Connected devices live in complex ecosystems that traditional security tools were never built to protect. They run on limited hardware, stay in service for years, sit in physically accessible places, and depend on tangled supply chains of third-party code. The number of connected devices worldwide is projected to reach around 32 billion by 2030 [verify before publishing: confirm current IoT device forecast and source], spanning consumer gadgets, medical equipment, industrial systems, and critical infrastructure. Each one is a potential entry point, and each shares a common weakness we will keep coming back to: nobody can secure what they cannot see.

What is a connected device security flaw?

A connected device security flaw is any weakness in a device's software, firmware, or settings that an attacker can exploit, such as a default password.

The term covers a wide range. It includes coding bugs like buffer overflows, design mistakes like unauthenticated network services, configuration errors like open debug ports, and supply-chain problems like a vulnerable open-source library buried in the firmware. What ties them together is exploitability: a flaw becomes a real risk the moment an attacker can reach it and do something with it. For connected products, that surface is large, because the device talks to networks, cloud services, mobile apps, and other devices.

What are the most common security vulnerabilities in IoT devices?

The most common IoT vulnerabilities are weak or default passwords, insecure network services, exposed interfaces, missing update mechanisms, and outdated third-party components.

That list is not our opinion. It closely tracks the OWASP IoT Top 10 [verify before publishing: confirm current OWASP IoT project URL], the recognized reference for connected device weaknesses, which OWASP compiled from real-world incidents. Here is how the most common flaws break down.

The last two rows are worth dwelling on. According to Palo Alto's Unit 42 IoT threat research, the large majority of IoT device traffic has historically been unencrypted [verify before publishing: confirm the current Unit 42 figure, often cited as 98%], and the outdated-components row is the one that quietly drives most of the others.

What are the most common vulnerabilities in consumer IoT devices like cameras, routers, and smart bulbs?

Consumer devices most often fail on default passwords, exposed app interfaces, and unpatched firmware, which is how cameras, routers, and smart bulbs get hijacked.

The pattern is consistent. A camera or router ships with a factory password, that password is public or guessable, and the device is exposed to the internet. Attackers scan for it, log in, and enlist the device into a botnet or use it as a foothold into the home or office network. A single weak device is enough: one vulnerable thermostat or doorbell camera can open a path to everything else on the same network. This is exactly the kind of exposure the UK's PSTI Act [verify before publishing: confirm PSTI link and in-force status] was written to stop, by banning universal default passwords on consumer connectable products.

How do hackers gain access to connected devices through firmware?

Hackers exploit firmware by extracting it, finding known vulnerabilities or hardcoded secrets in its components, then using unsigned updates to load malicious code.

Firmware is where the device's real behavior lives, and it is often the least scrutinized part of the product. An attacker with physical access can pull the firmware from a chip or a debug port. From there they analyze it for hardcoded passwords, private keys, and known-vulnerable open-source components. If the device accepts firmware updates that are not cryptographically signed, they can push their own malicious image and take control. This is why firmware-level analysis matters so much, and why a surface-level scan of the app or network is not enough. The vulnerabilities that cause the worst incidents are usually buried in binaries nobody inventoried.

What are recent examples of major smart home security breaches?

Recent smart home breaches include the 2024 Wyze incident, where about 13,000 users briefly saw strangers' camera feeds, plus repeated Ring doorbell hijackings.

The 2024 Wyze breach is a textbook case of the supply-chain angle. The cause was a third-party caching library Wyze had recently added; during a service outage it misbehaved and let roughly 13,000 users see thumbnails from other people's cameras, with about 1,500 tapping through to a stranger's image. Earlier, families whose Ring cameras were hijacked reported strangers speaking to them through the devices, leading to legal action and regulatory scrutiny. And going back further, the 2016 Mirai botnet enslaved hundreds of thousands of cameras and routers using nothing more than default passwords, then knocked large parts of the internet offline. Different devices, same root causes: weak credentials and unvetted code.

What are the security flaws in medical IoT and healthcare wearable devices?

Medical IoT flaws include unpatched legacy software, weak authentication, and vulnerable third-party network stacks, which can expose patient data or interfere with device function.

Healthcare raises the stakes because a flaw can affect safety, not just privacy. Connected infusion pumps, patient monitors, and wearables frequently run older software on long deployment cycles, and they often cannot be patched quickly without revalidation. Some of the most far-reaching examples came from shared components: the Ripple20 set of TCP/IP stack vulnerabilities affected a huge range of medical, industrial, and consumer devices at once, because they all embedded the same third-party networking code. We wrote about that ripple effect in our analysis of Ripple20, and it is the clearest illustration of why device makers, especially in medical devices, need to know every component inside their products.

Why are connected devices so hard to secure?

Connected devices are hard to secure because they have limited resources, long lifespans, physical exposure, and supply chains full of third-party code makers rarely see.

Each characteristic works against traditional security. Limited processing power and memory make strong encryption and monitoring difficult. Long lifespans mean a device shipped today will face threats that do not exist yet, often after the vendor has stopped issuing patches. Physical accessibility lets attackers bypass software controls entirely. And the supply chain is the quiet giant: modern firmware is mostly assembled from open-source and third-party components, and industry research consistently finds that the large majority of codebases contain at least one known open-source vulnerability, with hundreds of dependencies each [verify before publishing: confirm the current Black Duck OSSRA figures, often cited as 84% and ~595 dependencies]. You cannot manage risk in code you did not write and cannot see.

How does the EU Cyber Resilience Act affect connected device security?

The EU Cyber Resilience Act makes security mandatory for connected products: it bans default passwords, requires an SBOM and vulnerability handling, and mandates incident reporting.

The EU Cyber Resilience Act (CRA) applies to almost any product with digital elements sold in the EU, and it turns product security into a condition of market access. It requires secure-by-default configuration, which rules out shipped default passwords and unnecessary open ports. It makes a software bill of materials a binding legal requirement, the first such mandate anywhere. It requires manufacturers to handle vulnerabilities across the support period and to report actively exploited ones to ENISA. Penalties reach 15 million euros or 2.5% of global turnover. The dates matter because the reporting duties arrive well before full compliance.

The common thread is visibility. You cannot report whether a product is affected by a new vulnerability, or prove secure-by-default, without knowing what is inside it. That is why the SBOM sits at the center of the regulation.

How do you fix connected device security flaws?

Fix connected device flaws by starting with visibility: build a ground-truth SBOM from the device's firmware, then patch the vulnerabilities that are actually reachable.

Every control depends on knowing what you shipped. A software bill of materials built from the firmware itself, not from a spec or a partial source scan, turns an unknown mix of third-party and open-source code into an inventory you can act on. From there, you can match components against known vulnerabilities, and use reachability analysis to focus on the flaws that are genuinely exploitable rather than chasing every CVE. That approach is what a ground-truth software inventory is built to deliver, and it is the foundation for patching, monitoring, and CRA-style evidence alike.

How Finite State helps secure connected devices

At Finite State, we help manufacturers secure complex connected ecosystems by working from the shipped reality of the device. We combine deep binary analysis, continuous SBOM lifecycle management, and reachability-based vulnerability assessment so teams can find real exposure, fix what matters, and prove it. Whether you are preparing for the EU Cyber Resilience Act, strengthening your secure development lifecycle, or getting ready for penetration testing, our platform and advisory services are built for the realities of embedded and IoT systems.

Connected device security is not a one-time audit. It is a continuous workflow: see what you ship, verify it, prove it. To secure your connected devices with confidence, contact Finite State to schedule a consultation.