Updated July 13, 2025
In today’s connected healthcare ecosystem, encryption is vital for protecting sensitive patient data and securing medical devices—from infusion pumps to imaging systems. But attackers targeting medical devices don’t always break encryption with brute force. Instead, they exploit design flaws, weak implementations, and hardware-level vulnerabilities.
This article explores three real-world methods used to break encryption—and why medical device manufacturers must prepare for them as part of an FDA-ready cybersecurity program.
1. Brute Force Attacks on Medical Device Firmware
A brute force attack involves systematically guessing every possible key combination until the correct one is found. While modern encryption like AES-256 is theoretically immune to brute force due to key length, real-world devices often have flawed implementations that expose shortcuts.
Many medical devices use hardcoded or default encryption keys embedded in their firmware. A hacker can extract the firmware from a PCB, reverse engineer the code, and brute-force the encryption offline. For example, several infusion pumps have been found using weak AES implementations that could be cracked within hours using GPUs.
2. Side-Channel Exploits on Embedded Device Hardware
Side-channel attacks analyze a device’s physical characteristics—like power consumption, electromagnetic leaks, or timing patterns—while it performs encryption. These observations can be used to reconstruct secret keys without directly breaking the algorithm.
This attack vector is especially relevant for implantable or wearable medical devices. Researchers have demonstrated side-channel vulnerabilities in pacemakers and insulin pumps, showing that attackers could extract cryptographic keys simply by analyzing the device during normal operation.
Poor hardware shielding, predictable encryption routines, and lack of noise generation make medical devices more susceptible to these types of attacks if not mitigated in the design phase.
3. Cryptanalysis of Device Communication Protocols
Cryptanalysis involves exploiting known weaknesses in cryptographic algorithms or their implementation. Medical devices are sometimes built on outdated or customized cryptographic protocols that don’t meet modern security standards.
Examples include:
- Devices using deprecated algorithms like DES or RC4
- Reuse of static initialization vectors (IVs)
- Poor entropy in key generation
- Use of proprietary crypto instead of vetted open-source libraries
These flaws can allow attackers to decrypt or forge device communications, intercept data, or manipulate device behavior over wireless protocols like BLE or Wi-Fi.
How to Protect Medical Device Encryption
To defend against encryption attacks, medical device manufacturers should integrate cybersecurity early and follow FDA-aligned best practices:
- Use strong encryption standards like AES-256 for data at rest and TLS 1.3+ for data in transit
- Avoid custom cryptography—use vetted, FIPS-validated libraries
- Implement secure key generation, storage, and rotation mechanisms
- Conduct penetration testing to validate firmware and communication security
- Include encryption risks and controls in your Secure Product Development Framework (SPDF)
- Monitor third-party and open-source components with a complete Software Bill of Materials (SBOM)
FAQs: Medical Device Encryption & FDA Compliance
Q: What encryption standards does the FDA expect in medical devices?
The FDA encourages using NIST-recommended, FIPS-validated encryption such as AES-256 for data at rest and TLS 1.2+ for data in transit. The agency expects encryption controls to be documented in the premarket submission via the eSTAR cybersecurity section.
Q: Can the FDA reject a submission due to weak encryption?
Yes. If encryption is inadequately implemented or not covered in your threat modeling and SPDF, the FDA may issue deficiencies or reject the application outright. Encryption is considered a critical risk control for software of unknown provenance (SOUP), wireless interfaces, and cloud-connected features.
Final Thoughts
Hackers targeting medical devices don’t need to break encryption the hard way—they find shortcuts created by oversight, outdated libraries, or poor implementation. Whether through brute force, side-channel analysis, or cryptanalysis, these attacks can compromise patient safety and stall regulatory approval.
If you’re developing or updating a connected medical device, encryption can’t be treated as a checkbox—it must be validated, tested, and integrated into your full cybersecurity lifecycle.
Secure Your Device Before the FDA Asks
Blue Goat Cyber helps medical device manufacturers identify and fix encryption vulnerabilities before they impact patients—or trigger a deficiency notice from the FDA.
👉 Schedule your free medical device cybersecurity consultation today.