Partial CUI Compliance
1 NIST 800-171 gaps detected. Currently pursuing FedRAMP authorization. Not yet approved for CUI. Use with caution and document risk acceptance.
Mattermost
by Mattermost
FedRAMP Status
FedRAMP In Process
Impact Level
N/A
Category
Collaboration
Overview
Mattermost is an open-source messaging platform that can be self-hosted in government environments. It is pursuing FedRAMP authorization but is not yet approved for CUI without a documented risk acceptance.
CUI Risk Assessment
Currently pursuing FedRAMP authorization. Not yet approved for CUI. Use with caution and document risk acceptance.
Using Mattermost in a Defense Contractor Environment
Mattermost presents significant challenges for defense contractors handling CUI in collaborative environments. The platform typically processes technical drawings, contract specifications, proposal data, and engineering discussions containing controlled technical information (CTI) and export-controlled data under ITAR/EAR. Within a CMMC Level 2 authorization boundary, Mattermost would require full network segmentation, encryption at rest/transit, and comprehensive audit logging. The primary concern is NIST 800-171 control 3.13.8 (transmission confidentiality), as standard Mattermost deployments may not meet DoD encryption standards without additional hardening. DCMA/DIBCAC assessors specifically scrutinize collaboration tools during CMMC assessments, focusing on data flows, user access controls, and encryption implementations. Recent DCMA reviews have flagged organizations using non-FedRAMP authorized collaboration tools, particularly those processing technical data streams. Compensating controls must include network-level encryption, DLP monitoring, and documented risk acceptance from the authorizing official. The open-source nature provides transparency but requires significant security hardening expertise. Without FedRAMP authorization, contractors must implement enterprise-grade security configurations, including FIPS 140-2 validated encryption modules, centralized authentication via CAC/PIV, and comprehensive audit trails meeting DFARS 252.204-7012 requirements.
Deployment & Architecture
Deployment Model: Self-hosted (open-source)
Mattermost is pursuing FedRAMP authorization. Until authorized, this tool should not be used for CUI processing in production. Defense contractors should plan migration timelines and identify compensating controls.
Migration Guidance
Defense contractors must implement a 12-16 week migration strategy to achieve CUI compliance with Mattermost. Phase 1 (Weeks 1-4): Complete security assessment and architecture review, focusing on encryption standards and network segmentation requirements. Engage security engineering team to evaluate FIPS 140-2 compliance gaps and design hardened deployment architecture. Phase 2 (Weeks 5-8): Deploy hardened Mattermost instance with enterprise security configurations including TLS 1.3, AES-256 encryption, and integration with existing PKI infrastructure for CAC/PIV authentication. Configure audit logging to meet NIST 800-171 AU family requirements. Phase 3 (Weeks 9-12): Execute data migration using encrypted channels, ensuring CUI marking preservation and access control inheritance. Train users on CUI handling procedures within collaborative environments. Phase 4 (Weeks 13-16): Update System Security Plan (SSP) to reflect Mattermost within authorization boundary, document compensating controls in POA&M, and prepare CMMC assessment artifacts. Alternative compliant solutions include Microsoft Teams GCC High ($22-35/user/month), Slack Enterprise Grid on GovCloud ($15-25/user/month), or Element Enterprise for government ($8-15/user/month). Total migration costs estimate $150K-400K including licensing, professional services, and compliance documentation for 200-500 user organizations.
Migration Checklist
- 1ISSO shall document Mattermost as a non-compliant system requiring risk acceptance in the POA&M with specific reference to NIST 800-171 control 3.13.8 violation.
- 2System administrator must implement FIPS 140-2 Level 2 validated encryption modules for all Mattermost data transmission and storage components.
- 3Network security team shall configure network-level encryption using IPSec or TLS 1.3 tunnels for all Mattermost client-server communications.
- 4ISSO must update the authorization boundary diagram to clearly delineate Mattermost servers within the CUI processing environment boundaries.
- 5Contracts officer shall coordinate with government contracting officer representative (COR) to document risk acceptance for using non-FedRAMP authorized collaboration tool.
- 6System administrator must configure centralized authentication integration with existing PKI infrastructure to support CAC/PIV smart card access.
- 7ISSO shall implement comprehensive audit logging configuration to capture user activities, file transfers, and administrative actions per NIST 800-171 AU-2 requirements.
- 8Legal team must review data residency requirements and ensure all Mattermost data storage locations comply with DFARS 252.204-7012 covered defense information restrictions.
- 9ISSO must establish data loss prevention (DLP) monitoring rules to detect and prevent unauthorized CUI transmission through Mattermost channels.
- 10System administrator shall configure automated backup and recovery procedures with encryption for all Mattermost databases and file storage repositories.
Compliance Cross-References
Mattermost's current compliance gaps primarily impact NIST 800-171 System and Communications Protection (SC) family controls, specifically SC-8 (transmission confidentiality) and SC-13 (cryptographic protection). The violation of control 3.13.8 directly triggers DFARS 252.204-7012 clause requirements for adequate security measures protecting covered defense information. Within CMMC Level 2 assessment domains, this affects Identification and Authentication (IA), System and Communications Protection (SC), and Configuration Management (CM) practices. Assessors will evaluate cryptographic implementations, access controls, and audit mechanisms during Practice IA.L2-3.5.3 (multifactor authentication) and SC.L2-3.13.8 (transmission confidentiality) reviews. The lack of FedRAMP authorization creates cascading compliance issues across Access Control (AC) family requirements, particularly AC-3 (access enforcement) and AC-4 (information flow enforcement). Organizations must address these gaps through compensating controls documented in their System Security Plan and maintain continuous monitoring per NIST 800-171 CA-7 requirements until FedRAMP authorization is achieved.
NIST 800-171 Violations
Using Mattermost for CUI without FedRAMP authorization may violate these NIST 800-171 controls:
Need a CUI-Compliant Alternative?
Mattermost has 1 NIST 800-171 gaps. Get real-time alerts when compliant alternatives launch, plus AI-matched contract opportunities.
FedRAMP Compliant Alternatives
Related Compliance Assessments
Frequently Asked Questions
Is Mattermost FedRAMP authorized?
Not yet. Mattermost is in the FedRAMP authorization process. Its self-hosted option can be deployed on FedRAMP authorized infrastructure, but the SaaS version is not yet authorized.
Can I use Mattermost with CUI?
Mattermost is not yet FedRAMP authorized for CUI. If self-hosted on FedRAMP High infrastructure like AWS GovCloud, it may meet requirements with proper configuration and risk documentation.
Run a Full Tech Stack Audit
Check all your enterprise tools at once with our free CUI Compliance Auditor.
Launch CUI AuditorTrack Mattermost compliance monitoring with AI-powered intelligence
Signals matches SAM.gov opportunities to your profile, monitors regulatory changes, and alerts you before competitors. Free for 90 days.
Start Free — 90 Days