CMMC and the Hidden Risks in Your Legacy File Shares
CMMC and the Hidden Risks in Your Legacy File Shares
Blog Article
Legacy file shares may feel like a safe, familiar place for your team’s documents—but for defense contractors pursuing CMMC compliance, they’re often a hidden liability. Unstructured, unmonitored, and full of forgotten data, these file shares are a magnet for risk when Controlled Unclassified Information (CUI) is involved.
Why Legacy File Shares Are a Problem
Many organizations still rely on on-premises file shares or outdated SharePoint setups to store business-critical information. These environments:
Lack modern access controls and auditing
Allow broad, unmonitored file access
Store unclassified and CUI data side-by-side
Are often excluded from modern data loss prevention (DLP) strategies
These conditions can result in non-compliance with NIST 800-171 controls related to access, encryption, and auditing.
CMMC Compliance Starts with Visibility
You can’t protect what you can’t see. Legacy file shares typically lack:
Automated classification of sensitive data
Detailed activity logging
Role-based access enforcement
As a result, CUI may be exposed to unauthorized users without anyone knowing—a direct risk to CMMC Level 2 compliance.
What Needs to Happen
Before migrating to Microsoft 365 GCC High, contractors must:
Identify and inventory all legacy file shares
Scan for and label CUI using automated discovery tools
Remove unnecessary or outdated files
Apply access control policies that meet CMMC standards
This not only protects your data, but reduces scope for compliance audits.
GCC High as the Destination
Microsoft 365 GCC High provides the modern capabilities your legacy file shares lack:
Sensitivity labels and data classification through Microsoft Purview
Role-based access and conditional access via Azure AD
Automated auditing and activity logging
Integrated DLP and threat protection
Migrating CUI out of legacy file shares and into this environment is a major compliance win.
Start with the Right Partner
GCC High migration services help uncover hidden CUI, clean up outdated storage environments, and move your data securely to the cloud—all with CMMC compliance in mind.