Not CUI Compliant
4 NIST 800-171 gaps detected. Not FedRAMP authorized. Using this tool for CUI creates compliance violations under NIST 800-171 and DFARS 252.204-7012.
ProtonMail
by Proton
FedRAMP Status
Not FedRAMP Authorized
Impact Level
N/A
Category
Overview
ProtonMail is a Swiss-based encrypted email provider focused on privacy. Despite its strong encryption, it is not FedRAMP authorized and data residency outside the US disqualifies it for CUI handling.
CUI Risk Assessment
Not FedRAMP authorized. Using this tool for CUI creates compliance violations under NIST 800-171 and DFARS 252.204-7012.
Deployment & Architecture
Deployment Model: Cloud SaaS (vendor-hosted)
ProtonMail has no FedRAMP authorization on record. DFARS 252.204-7012(b)(2)(ii)(D) requires an external cloud service provider to meet security requirements equivalent to the FedRAMP Moderate baseline — an authorization is the straightforward way to show that, but it is not the only one. Without one, the burden is on you to establish, document, and defend equivalency, and to meet the clause's incident-reporting and media-preservation obligations. Most contractors find an authorized alternative cheaper than carrying that burden.
Migration Checklist
- 1ISSO: Conduct immediate CUI inventory review of all ProtonMail accounts within 1 week
- 2Contracts team: Review active contracts for CUI email requirements and notify contracting officers of migration timeline within 2 weeks
- 3ISSO: Select FedRAMP High authorized email replacement (O365 GCC High/Google Gov) and update authorization boundary documentation within 3 weeks
- 4Sysadmin: Export all CUI emails from ProtonMail using data export tools, maintaining classification markings within 4 weeks
- 5ISSO: Update System Security Plan removing ProtonMail from boundary and adding compliant email solution within 5 weeks
- 6Sysadmin: Deploy and configure replacement email system with CUI-appropriate encryption and DLP policies within 6-8 weeks
- 7ISSO: Conduct user training on new email system CUI handling procedures within 9 weeks
- 8ISSO: Submit updated SSP to AO and document ProtonMail decommissioning in POAM closure within 10 weeks
NIST 800-171 Violations
Using ProtonMail for CUI without FedRAMP authorization may violate these NIST 800-171 controls:
Need a CUI-Compliant Alternative?
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FedRAMP Compliant Alternatives
Related Compliance Assessments
Frequently Asked Questions
Is ProtonMail FedRAMP authorized?
No. ProtonMail is not FedRAMP authorized. Its servers are located in Switzerland, which does not meet US data residency requirements for CUI.
Can I use ProtonMail with CUI?
No. Despite end-to-end encryption, ProtonMail lacks FedRAMP authorization and US data residency, creating NIST 800-171 violations for CUI handling.
What is a compliant alternative to ProtonMail?
Microsoft 365 GCC High (FedRAMP High) and Google Workspace Government (FedRAMP Moderate) are authorized email platforms for defense contractors.
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