Medical Device Cybersecurity Testing Tools for FDA Premarket Submission

Getting a medical device cleared by the FDA today means cybersecurity is not optional paperwork. The agency's 2023 guidance on cybersecurity in medical devices - and the authority granted under the Consolidated Appropriations Act of 2023 - requires manufacturers to submit a software bill of materials, a cybersecurity risk management plan, and evidence of testing that demonstrates the device behaves safely under adversarial conditions. That last part is where a lot of teams hit a wall.

Static analysis and manual code review are table stakes. But FDA reviewers increasingly want to see that you tested the running device - not just the source code. That distinction matters more than it sounds.

Why Static Analysis Alone Is Not Enough for FDA Submissions

Static analysis tools reason about what the code says. They flag known-bad patterns, outdated dependencies, and coding errors. They are genuinely useful, and they belong in your submission package.

But FDA premarket guidance asks a different question: how does the device behave when it receives unexpected, malformed, or adversarially crafted input? A static tool cannot answer that. It never touches the firmware executing on hardware. It never sends a packet.

The gap matters most for:

• Networked devices communicating over Wi-Fi, Bluetooth, or proprietary RF protocols
• Firmware-level interfaces that handle binary protocol framing
• CAN bus / embedded targets in combination devices or electromechanical systems
• Serial and hardware debug interfaces that can be exercised during a premarket security assessment

For these attack surfaces, dynamic testing - testing the device while it runs - is the relevant evidence.

What Dynamic Fuzzing Produces That FDA Reviewers Can Use

Fuzzing is a form of dynamic testing that sends a large volume of semi-random, mutation-based, or grammar-driven inputs to a target and monitors for crashes, hangs, unexpected behavior, or safety-relevant state changes.

For a premarket submission, well-structured fuzzing produces:

• A documented set of attack surfaces tested
• A corpus of test cases and the inputs that triggered findings
• Reproducible evidence that known-bad inputs were exercised
• Coverage over protocol state machines, not just individual fields

This maps directly onto what FDA guidance describes as "testing under simulated attack conditions" and supports the narrative your cybersecurity risk management plan needs to tell.

Penzzer: Dynamic Fuzzing for Medical Devices and Embedded Targets

Penzzer is a dynamic fuzzing tool built specifically for the targets that matter in medical device submissions - IoT firmware, CAN bus, and embedded protocols. It attacks behavior on the running device, not static representations of the code.

The distinction in scope is intentional: Penzzer is not an API fuzzer or a web application scanner. It is designed for the firmware and protocol layer - the attack surface that is hardest to test with general-purpose tools and most relevant to FDA cybersecurity submissions.

Penzzer covers:

• Wi-Fi and wireless protocol fuzzing - configurable per protocol, interface, and channel; supports access-point-mode fuzzing with security configuration
• Firmware-level targets - the device as it runs, not a simulation of it
• CAN bus and embedded interfaces - relevant for combination products and electromechanical medical devices

The setup is straightforward: tell Penzzer what you want to fuzz - the target, the protocol, the interface configuration - and it handles the campaign from there.

What to Look for in a Fuzzing Tool for FDA Work

Not every fuzzer is appropriate for regulatory evidence. When evaluating tools for a premarket submission package, consider:

Target fidelity - Does the tool test the actual device or a software model? On-device testing produces more credible evidence.

Protocol specificity - A fuzzer that understands the structure of the protocol produces more meaningful findings than one that sends pure random bytes. Grammar-aware fuzzing reaches deeper into protocol state machines.

Reproducibility - Can you reproduce a finding exactly? FDA submissions require that identified vulnerabilities be documented and, where remediated, that remediation can be verified. Your tool needs to give you reproducible test cases.

Coverage reporting - Evidence of test coverage strengthens your submission narrative. What surfaces were exercised? What was out of scope and why?

Fit for embedded targets - General-purpose API fuzzers do not translate to CAN bus or firmware interfaces. Choose a tool built for the target class.

Fitting Fuzzing Into Your Premarket Timeline

Cybersecurity testing for FDA submissions is not a last-minute activity. The time to start is during design verification, not in the weeks before submission.

A practical sequence:

1. Identify attack surfaces early - Wi-Fi, Bluetooth, CAN, serial debug interfaces, firmware update mechanisms
2. Run initial fuzzing campaigns during DVT - find issues when you can still fix them
3. Document findings and remediations - the submission package needs the full story, not just a clean final state
4. Repeat targeted fuzzing after firmware changes - regression coverage for any significant software revision
5. Compile the evidence package - test corpus, findings, remediations, residual risk rationale

Starting early means findings become design improvements rather than submission delays.

Next Steps

If you are preparing a medical device for FDA premarket submission and need to demonstrate dynamic security testing of the device's firmware and embedded protocols, Penzzer is worth a conversation. The starting point is simple: describe what you want to fuzz - the target, the protocol, the interface - and the team will work with you from there.

Learn more or start a conversation at penzzer.com.

Published 11 October 2026

This post is about Penzzer.