Hardening Fabric Warehouse Security

Description

Learn how to secure Fabric Data Warehouse from the ground up. This session covers end-to-end practices—from secure connectivity and authentication to auditing, monitoring, and governance—highlighting new features that strengthen compliance, visibility, and trust at scale.

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Hardening Fabric
Warehouse Security
Building Layered Defense from Authentication to Governance
About your Speakers
Freddie Santos
Senior Product Manager
Fabric Warehouse
Sam Debruyn
Freelance Data Platform Architect
MVP Microsoft Fabric
Our mission is to “make sure you never make the news—for the wrong reasons”
Session Roadmap
“To build a truly secure and compliant Warehouse; security must be approached in layers”
▪ Cybersecurity Threats, Risks, and Impacts on Fabric Data Warehouse
▪ Layers of Protection
2.1
▪ Identity is the
Foundation
2.2
▪ Network
Restricted:
Reducing Attack
Surface
2.3
Data Protection:
Continuous
Encryption
2.4
2.5
Policy Enforcement:
Limiting Data
Exposure
Fully Observable &
Governed
The Stakes Have Never Been Higher
3,322
Data Breaches Tracked in 2025 in the US alone — An All-Time High
About $34 billion dolars
In financial loses – US only.
$10.22M*
246 days
average cost of a single data breach
breaches due to incorrect security
configurations of cloud
components
needed on average to
identify and contain the
breach
Attackers are no longer breaking in —they're simply logging in with stolen credentials, making identity
and configuration hardening your first line of defense

  1. Fabric is disconnected from
    the public internet
    Azure VNets
    Peering
  2. Every users needs to connect to
    the private network to get access
    on every device
    Azure Private Link (Tenant
    Level)
    Private
    Endpoint
    Customer VNet1
    Inbound
  3. No longer able to load resources
    locally (slower reports)
    OneLake
    Microsoft Fabric
  4. Increases ExpressRoute bandwidth
    and added costs for Private Links
    Disabled
  5. Several product limitations
    (like on-prem data gateway)
    Public Access
    Workspace level Private Link for Fabric
    Perimeter Network Security for your workspace
    On-prem
    ExpressRoute
    / VPN
    Azure VNets
    Fabric Tenant
    Workspace A
    Peering
    Azure
    Private Link
    Private
    Endpoint
    Lakehouse
    Warehouse
    Notebook
    Workspace B
    Private Data
    Access
    Semantic
    Model
    Entra Conditional
    Access Policies
    Report
    (Tenant Level)
    (Workspace Level)
    OneLake
    Spark Job Definition
    Pipeline
    KQL Database
    Customer VNet1
    Disabled
    Enabled (with
    Entra Conditional
    Access Policies)
    Public Access
    Outbound Access Protection
    Sealing the Vault
    Fabric Workspace
    ▪ Complete Exfiltration Prevention: OAP ensures
    that even if a system is compromised, data
    cannot be leaked to unauthorized public
    endpoints or non-whitelisted external tenants.
    Outbound Rules
    ▪ Granular Trusted Routing: You maintain strict
    control by explicitly allowing connections only to
    validated resources, such as trusted Fabric
    Workspaces or specific ADLS Gen2 paths.
    Outbound Rules
    ▪ Operational Integrity: By blocking unauthorized
    COPY INTO or OPENROWSET attempts by
    default, you ensure that data movement only
    occurs between pre-approved, secure
    environments.
    Lakehouse
    COPY INTO
    COPY INTO
    Warehouse
    OPENROWSET
    Denial List Rules
    Allowed List Rules
    Extreme Network Protection
    Outbound Access Protection +
    Workspace Private Link
    Outbound Access Protection (OAP): Blocks
    unauthorized data export from the Data
    Warehouse.
    Workspace Private Link: Ensures inbound
    access is limited to private, secure network
    boundaries.
    Together: They create a zero-trust boundary
    around your workspace, preventing sensitive
    data from leaking in or out.
    Whether you use TPL or WS PL or use Firewall Rules to access Fabric over
    public endpoint, Entra Conditional Access is a must !
    Layer 3: Encryption
    The Ransomware Crisis - Network Protection as Foundation
    Ransomware Attack Growth 2023-2025
    10.0
    9.0
    Victims (thousands)
    8.0
    44%
    75%
    $5M+
    of breaches
    involve
    ransomware
    of attacks are
    identity-based
    average
    recovery cost
    7.0
    ▪ Network breaches are initial entry points—phishing (16%) and
    credentials (12-14%) bypass perimeter defenses
    6.0
    5.0
    ▪ Credential theft surged 800% in 2025: 1.8B credentials stolen
    via infostealer malware post-compromise
    4.0
    3.0
    2.0
    ▪ Attackers stay hidden for months (63% for 6+ months),
    mapping cloud resources and stealing credentials
    1.0
    0.0
    Year
    ▪ Once inside, attackers conduct reconnaissance to identify
    cloud connections and privileged accounts
    Source: The State of Ransomware in the U.S.: Report and Stati...
    ▪ Attack chain: network breach → credential theft → cloud access
    → encryption
    Fabric Customer Managed Keys (CMK)
    Create Keys
    Generate and manage keys in Azure Key Vault with full
    lifecycle control
    ▪ Fabric encrypts all data by default with Microsoft-managed keys, providing strong
    baseline security across workspaces
    Connect Workspace
    Link Fabric workspace to Key Vault for encrypted key
    access
    ▪ CMK adds encryption layer via envelope encryption—your Key Vault key encrypts
    Microsoft's data encryption keys
    ▪ Keys stay in your Key Vault—Fabric accesses via secure APIs with logged, policyvalidated calls
    ▪ Workspace-level granularity lets you apply enhanced encryption selectively to sensitive
    environments
    Automatic Encryption
    OneLake data and metadata encrypted using your
    keys automatically
    Control Access
    Manage permissions, rotation, and revocation
    independently
    Audit Everything
    Monitor all key usage via Azure Key Vault logs
    CMK Implementation in Fabric Warehouse
    OneLake Data
    All persisted data encrypted with your
    CMK including tables, Delta Parquet
    files, and analytics datasets
    Encryption
    Layers
    Zero
    Performance
    Impact
    Ephemeral
    Compute
    Auto-clearing caches
    Warehouse Metadata
    Table definitions, stored procedures,
    functions, and schema information
    encrypted with your key
    Protection depth
    No speed reduction
    ▪ SQL frontend encrypts all metadata including table definitions, views, and
    functions using your key to protect schema information
    ▪ All OneLake data uses your Azure Key Vault key through envelope encryption,
    providing comprehensive protection for persisted information
    Backend Compute
    Ephemeral caches use Microsoftmanaged keys and auto-clear after
    sessions, no data persists
    ▪ Backend compute processes queries in ephemeral cache environments that
    auto-evict content after use, with no data at rest
    ▪ Once enabled, both existing and new Warehouse items automatically use your
    encryption keys without manual configuration
    Demo
    CMK
    Layer 4: Limiting Data Exposure
    Why Ingestion Must Be Controlled
    Arbitrary storage path access
    Silent data exfiltration risk
    Threat Vectors
    ▪ COPY INTO & OPENROWSET
    Only 2 SQL commands with external access in Data Warehouse
    ▪ Abuse - Arbitrary Storage Paths
    Attackers specify external storage locations as data sources,
    bypassing access controls and reading unintended files
    ▪ High-Bandwidth Attack Channel
    Ingestion processes large volumes rapidly, enabling significant data
    movement without triggering monitoring
    ▪ Privilege Escalation Vector
    COPY INTO runs with elevated permissions, making it attractive for
    unauthorized data access
    Corrupted analytical datasets
    Complex incident response
    Real Harm Impact
    ▪ Silent Data Exfiltration to Attacked-Controlled Warehouses
    Sensitive data copied to attacker-controlled storage without
    detection, appearing as legitimate operations
    ▪ Compliance Violations
    Unauthorized data movement creates regulatory failures, legal
    penalties, and breach notification requirements
    ▪ Dataset Corruption and Integrity Loss
    Malicious data injection undermines analytical integrity, leading to
    incorrect business decisions
    ▪ Loss of Trust and Incident Response Complexity
    Discovered abuse erodes stakeholder trust and requires complex
    forensic investigations
    Hardening Ingestion in Warehouse
    Fabric Warehouse implements defense layers to control ingestion operation
    Validated OneLake paths only
    System-controlled staging
    Outbound Access Protection
    Identity-scoped permissions
    ▪ Source Validation: Only validated OneLake paths from trusted workspaces
    eliminating arbitrary storage access.
    ▪ Network Protection: Private Link limits inbound access while Outbound
    Access Protection prevents data exfiltration.
    ADLS gen2
    ▪ Identity Checks: COPY INTO evaluated under Entra identity with least
    Warehouse table
    privilege (Granular Insert Permission).
    Google Cloud Storage
    ▪ Audit Trail: All operations logged with staging and execution tracing for
    OneLake Storage
    forensics-ready compliance reporting.
    AWS S3
    Layer 4: Data Protection – Tight Permission Controls
    Fine-Grained Data Protection
    GRANT/DENY Columns
    Masking Functions
    ● Column-Level Security (CLS): Use GRANT and DENY statements to control access
    to columns with sensitive information
    ● Dynamic Data Masking (DDM): Apply functions that obfuscate sensitive data,
    showing 'XXX-XX-1234' instead of full social security numbers
    ● Row Level Security: Choose Role-Based Filtering to define filter conditions based
    on user identity, role membership, or attributes to automatically restrict rows
    ● Prevent Elevated Access: Designate groups, roles and permission to the
    granular level, avoiding granting more access than users should have.
    ● Layered Approach: Combine RLS, CLS, and DDM to create multiple barriers
    against attacks
    Don't Ignore SQL Security: The Principle of Least Privilege
    ▪ Move Beyond "All or Nothing": Avoid granting high-level administrative roles to general users.
    ▪ Precision Control: Use explicit GRANT, DENY, and REVOKE statements at the object level (Tables, Views, Stored Procedures).
    ▪ Layered Defense: Apply Row-Level Security (RLS) and Column-Level Security (CLS) to protect sensitive data cells within a
    shared table.
    T-SQL Security – Best Practices
    CRITICAL!
    SQL Security is enforced exclusively via TDS Endpoints. Accessing the underlying file
    system through Direct Lake or Shortcuts bypasses these SQL-level permissions entirely.
    *Sneak Peak: We have a say about this later
    Layer 5: Monitoring and Detection
    Monitoring & Detection: The "Assume Breach" Foundation
    Correlating Control Plane & Data Plane telemetry to validate Zero Trust.
    Control Plane
    Data Plane
    ▪ Full SQL Audit: Capture comprehensive T-SQL
    ▪ Workspace Lifecycle: Trace all creation, deletion,
    and configuration changes of the workspace.
    command text, execution parameters, and precise
    ▪ Security Controls: Audit who enabled Customer
    ▪ Access Forensics: Enable deep "Who, When, and
    Managed Keys (CMK) or modified any workspace
    What" tracing for every granular data interaction.
    timestamps.
    setting.
    ▪ Integrity Validation: Verify that data access aligns
    with the governance and security controls.
    Control Plane: Fabric & Purview Governance
    Governing the Fabric Ecosystem
    ▪ Platform Activity Strategy: Track high-level operations such as
    CreateWorkspace, UpdateCapacity, and DeleteArtifact (Lakehouses,
    Pipelines, Warehouses) to maintain environment integrity.
    ▪ Metadata Traceability: Utilize the Microsoft Fabric Operation List to
    capture the "Who" and "When" for structural changes, such as
    moving artifacts or changing workspace permissions.
    ▪ Purview & Label Governance: Monitor sensitivity label changes
    (upgrading/downgrading) and Data Loss Prevention (DLP) policy
    triggers to ensure data remains classified correctly.
    ▪ Administrative Forensics: Audit "Power User" actions, including
    capacity setting modifications and tenant-level configuration drifts
    that could bypass lower-level security testing) that precede targeted
    data extraction
    SQL Audit Logs– From
    Configuration to Forensics
    Knowing the questions help you find the answers
    ▪ Capture Strategy: Focus on "high-signal" Action Groups—
    BATCH_COMPLETED, SCHEMA_OBJECT_CHANGE—to
    bridge the gap between Control Plane metadata and Data
    Plane execution.
    ▪ The Forensic Result: Leverage sys.fn_get_audit_file_v2 to
    extract the Who (server_principal_name), When
    (event_time), What (statement), and How (session_id) for
    every data interaction.
    ▪ Retention Policy: Implement a tiered retention strategy:
    30–90 days in hot storage for immediate forensic response
    and 1–7 years in cold storage (Azure Archive) to satisfy longterm compliance and "Assume Breach" look-back
    requirements.
    Demo
    SQL Audit Logs
    Best Practices: Incident Investigation & Replay
    Closing the Loop – From Logs to Actionable Forensics
    ▪ Reconstruction Strategy:
    Identify compromised accounts and unusual access patterns by
    cross-referencing authentication logs with specific query
    execution histories.
    ▪ Detecting Malicious Intent
    Detect lateral movement by tracking GRANT operations, role
    membership changes, and subsequent attempts to access
    previously restricted resources.
    ▪ Systematic Timeline Analysis:
    Query audit logs chronologically to map the entire attack chain,
    from initial unauthorized access through privilege escalation to
    final data exfiltration.
    ▪ Beyond Native Queries:
    Use Semantic Link (SemPy) to export audit files into a dedicated
    Fabric Lakehouse to bypass standard log retention limits and
    create a permanent, queryable "Forensic Vault.“
    ▪ Pattern Recognition:
    Perform query pattern analysis on captured T-SQL text to
    identify reconnaissance activities, such as schema enumeration
    or permission testing, that precede an attack.
    ▪ Root Cause & Scope Assessment
    Trace malicious activity back to the initial entry point, whether it
    was a compromised credential, a misconfigured permission, or a
    vulnerable application.
    .
    *Determine the exact scope of data exposure by correlating query
    logs with table sensitivity classifications and data volume metrics
    Closing
    Building Comprehensive Warehouse Security - Recap
    ▪ Identity as Foundation:
    Strong authentication reduce the risk of credential-based attacks that
    represent the primary breach vector
    ▪ Network Isolation Reduces Attack Surface:
    Create zero-trust boundaries that force attackers through monitored
    chokepoints and prevent data exfiltration
    ▪ Data Policies Limit Blast Radius:
    Ensure that even compromised accounts cannot access all sensitive
    data, containing damage from successful breaches
    ▪ Monitoring Enables Detection and Response:
    Comprehensive audit logging with provides visibility to detect
    anomalous behavior and respond before significant data loss
    ▪ Defense in Depth Philosophy:
    Each security layer compounds difficulty for attackers
    If you are starting today, plan for a zero-trust architecture. Prioritize
    Layer 1 (Identity) with strict Least Privilege and Layer 5 (Monitoring)
    as your non-negotiable pillars. These ensure that no identity has
    more permission than necessary and the network has the right
    controls in place—no exceptions
    What's Next: Security Roadmap
    Continuous innovation in security capabilities to address evolving threat landscape
    Granular Data Lineage
    Column-level lineage showing sensitive data flow
    OneLake Security for DW
    Support OneLake Security with Fabric DW
    Improved SQL Security Experience
    Improved experience, and traceability for security
    management on Fabric DW
    SQL Audit Logs Improvements
    Improved navigation experience, introducing predicate
    filtering and more.
    COPY INTO support Workspace Identity
    Support COPY INTO operations to support the Workspace
    Identities
    ..and more
    Quick Survey:
    Tell us what works — and what does
    not — in Fabric Data Warehouse!
    https://aka.ms/fabric-data-warehouse-survey
    It’s your time!
    Sound off.
    The mic is all yours.
    Influence the product roadmap.
    Join the Fabric User Panel
    Join the SQL User Panel
    Share your feedback directly with our
    Fabric product group and researchers.
    Influence our SQL roadmap and ensure
    it meets your real-life needs
    https://aka.ms/JoinFabricUserPanel
    https://aka.ms/JoinSQLUserPanel
    References
    [1] Microsoft Entra Authentication in Fabric Data Warehou...
    [2] About private Links for secure access to Fabric - Mic...
    [3] 50 Identity And Access Security Stats You Should Know...
    [4] Identity Theft Resource Center 2025 Annual Data Breac...
    [5] Identity Security: Cloud’s Weakest Link in 2025 | CSA
    [6] Connect to your most sensitive data with end-to-end n...
    [7] Workspace-Level Private Link in Microsoft Fabric (Gen...
    [8] Track user activities in Power BI - Microsoft Fabric | Microsoft Learn
    [9] Frequently Asked Questions (FAQ) · microsoft/semantic-link-labs Wiki