FDA cybersecurity deficiency-letter response for medical devices
The most expensive submission is the one you file twice, and a deficiency letter is usually how teams find out.
A hold letter needs a complete response, not another document checklist. Medcrypt helps your team interpret the request, address evidence gaps, and prepare a response informed by former FDA reviewers.
The gaps behind cybersecurity deficiencies
Your letter determines which risk, evidence, and support gaps need attention.
Medcrypt's published deficiency analyses identify recurring gaps in risk management, security evidence, and lifecycle planning. The letter determines which gaps matter for your device.
Risk and threat models
Explain device risks, interoperability, and third-party software in your risk evidence.
Understand FDA stock deficienciesRisk management and threat-model gaps
A missing risk-management plan, incomplete threat model, or unclear treatment of interoperability and third-party software leaves reviewers without a complete account of device risk.
SBOM and vulnerabilities
Connect software components, dependencies, and known vulnerabilities to device risk.
See the engineering responsibilitiesIncomplete SBOM and vulnerability evidence
Software components, dependencies, support status, and known vulnerabilities need to be accounted for. An SBOM without the associated risk assessment does not explain how those vulnerabilities affect the device.
Testing and disposition
Document mitigation or residual risk, with retesting evidence for fixes.
Read the 2026 deficiency lessonsTesting findings without a documented disposition
A penetration-test report alone does not close the loop. Findings need mitigation or a justified residual-risk decision, with retesting evidence for fixes and testing that reflects the production-equivalent system.
Controls and architecture
Explain authentication, cryptography, logging, resiliency, and updateability in the architecture.
See the regulatory responsibilitiesSecurity controls and architecture left unexplained
Authentication, authorization, cryptography, logging, resiliency, and updateability need a clear architectural explanation. Missing controls or unexplained design choices can leave questions that documentation alone cannot resolve.
Requirements to testing
Connect security requirements and risks to implemented controls and verification.
Understand cybersecurity approval delaysBroken traceability from requirements to testing
Reviewers need evidence that security requirements and identified risks connect to implemented controls and verification results. Separate documents do not help if that connection is missing.
Labeling and support
Document secure configuration, connectivity, patch support, and vulnerability-management plans.
See the leadership responsibilitiesUnclear labeling and postmarket support plans
Secure configuration instructions, connectivity disclosures, patch support, and vulnerability-management plans explain how security continues after release. These need engineering, regulatory, and leadership ownership.
Turn the request into a supported response
Work through each deficiency with a clear plan and supporting evidence.
Your response needs to address each deficiency clearly, with a narrative and the evidence behind it. We help you focus the work across regulatory and engineering teams.
Interpret the request
Identify missing evidence and unclear explanations with former FDA reviewer guidance.
Interpret each request against the existing evidence
Medcrypt reviews the letter and submission to distinguish information that is missing, information that already exists, and information that needs a clearer explanation. Former FDA reviewer experience informs that assessment.
Plan the response
Separate documentation, design, and testing work against the response deadline.
Define a response plan with your teams
We help regulatory, engineering, and product-security teams identify the work behind each deficiency. The plan separates narrative changes from design changes or additional testing and works back from the response deadline.
Support the remediation
Connect corrective work to risk assessments, threat models, SBOMs, and testing.
Connect remediation to supporting evidence
We help clarify the right-sized corrective approach and the documentation needed to support it, including risk assessments, threat models, SBOMs, and security testing. Responses need evidence, not only an assurance that a gap was addressed.
Prepare the response
Organize the narrative and evidence package; your team decides to submit.
Prepare a clear, complete response
Medcrypt supports the response narrative and evidence package for your FDA submission. Your team retains the decision to submit and the communication record, with readiness for further FDA clarification.
Further reading
- FDA is issuing deficiency letters - why you should care (Part 1/4)
- Product Engineers’ Approach to FDA Stock Deficiency Letters (Part 2/4)
- Regulatory Affairs’ Approach to FDA Stock Deficiency Letters (Part 3/4)
- Directors, VPs, and C-Suite Executives’ Approach to FDA Stock Deficiency Letters (Part 4/4)
- Navigating the 2026 FDA Cybersecurity Landscape: Lessons from the "Top Deficiencies"
Questions about your deficiency response
It is a request for additional information needed to evaluate the cybersecurity evidence in a medical device submission. Stock deficiencies use common language that reviewers tailor to the device. For a 510(k), an additional-information request puts the review on hold until the manufacturer responds.
No. The first step is to determine whether evidence is missing, already exists but was not included, or needs clarification. Some gaps can be addressed with a clearer narrative or supporting documentation. Others need design changes, additional testing, or remediation evidence. The response depends on the specific request and device.
For a 510(k) additional-information request, FDA's current policy generally allows 180 calendar days for a complete response. Medcrypt reports that customers using its deficiency-response support typically respond in 45 to 60 days.
Regulatory affairs should coordinate the response and submission evidence. Engineering and product-security teams need to address technical gaps, testing, and risk documentation. Leadership needs to allocate qualified people and budget for the work. Medcrypt supports these teams with deficiency-response guidance informed by former FDA reviewers.