The exponential growth of cloud adoption has expanded the traditional security perimeter beyond on-premises data centers to distributed and ephemeral environments. To effectively defend cloud assets in the face of rising threats, organizations need a new security paradigm centered on visibility and granular enforcement – commonly known as Zero Trust Architecture.
In this article, we’ll examine what led to the Zero Trust model along with practical steps for implementing key principles across public, hybrid, and multi-cloud deployments. We’ll also look at top scenarios where Zero Trust delivers improved cloud security and compliance.
Shortcomings of the Classic Security Model
To understand the necessity for Zero Trust’s granular controls, we first need to explore issues that emerged as security teams applied aging models designed for static data centers to cloud environments:
Perimeter-focused Controls Fail
Workloads constantly move, scale, and change within public clouds, making hard network perimeters obsolete.
Trust but Verify is Risky
The assumption of trusted access once users and workloads were on a corporate network led to free reign inside the perimeter making lateral attacker movement easy.
Deep Visibility Lost
Losing line of sight into complex inner-workings of application and data connections inside cloud providers highlights blindspots.
Cloud Velocity Prevents Manual Policy Changes
Slow and complex manual security configuration changes failed to keep up with the pace of growth and change in cloud environments.
Inconsistent Operations and Risk
Federated teams independently managing deployments with disjointed tools resulted in fragmented visibility, policy gaps, and improper access between interconnected cloud assets.
Facing these realities, organizations recognized the need to shift from trusting network constructs to verifying all access to cloud assets and environments themselves within a unified control fabric. This gave birth to the Zero Trust Model.
Key Capabilities of the Zero Trust Model
Here are fundamental Zero Trust principles critical to securing modern cloud environments:
Maintain an Asset Inventory
Discover a census of all cloud infrastructure, services, data stores, code repos, APIs and applications deployed across public and hybrid cloud environments.
Map Asset Dependencies
Understand interconnectivity and data flows between various cloud applications, services, and infrastructure components critical to system functions.
Strengthen Identity Governance
Standardize identity providers, roles, access policies, and enforcement across multi-cloud environments to prevent privilege and configuration sprawl.
Enforce Least Privilege Controls
Typical excessive permissions found within clouds lead to overentitled insiders, malicious access, and unnecessary exposure. Strictly enforce minimal access.
Inspect and Log Traffic
Unlock visibility into communications, data movement, and API calls between cloud services, regions, VPCs, users, and on-prem environments which are opaque to tools today.
Employ Adaptive Access Policies
Set context-aware access policies that consider user identity, device security, behavior patterns, sensitivity of data/operations, and environmental factors before allowing connections.
Continuously Validate Security Controls
Given frequent cloud changes, repeatedly check that configurations match intended policies across IAM, data stores, compute, network controls. Remediate drift.
With these Zero Trust pillars in place, organizations gain granular visibility, segmentation, and least privileged access strictly on a verified need basis across cloud assets–neutralizing attacks.
Embracing Zero Trust in Key Cloud Scenarios
Here are critical cloud security use cases to prioritize Zero Trust principles:
Securing Admin and Privileged Access
Conditional access policies that require multi-factor authentication (MFA), passwordless credentials secured in vaults, privileged access management (PAM), endpoint integrity checks and monitoring of admin actions restrict standing elevated privilege risks.
Containing Lateral Attacker Movement
Prevent attackers from advancing East-West internally post-breach by restricting communications across cloud assets to least privilege modes and data flows mapped to known good activity baselines only.
Protecting Sensitive Cloud Data Stores
Tag sensitive assets like proprietary databases in object storage or personal data. Using sensitivity labels to dynamically apply strong access controls, encryption requirements, activity monitoring, masking, and usage restrictions centered on protecting data over perimeter constructs.
Securing Cloud Inter-Service Communications
Map and authorize connectivity between serverless functions, containers, leaf services to core control plane functions based on policy guardrails. Detect and block unexpected calls to prevent dominance over authentication, permissions and secrets management services.
Coordinating Security Across Federated Teams
Unify visibility, access governance, configurations, logs and alerts under common data models and policies across centralized and distributed cloud teams to eliminate tool and control gaps that introduce risk to interconnected environments.
As these scenarios illustrate, embracing Zero Trust renders network locations and constructs irrelevant by focusing security on the users, workloads, APIs and data while managing seamless controls across hybrid IT.
Driving Value From Cloud Zero Trust Investments
Here are key measures to quantify the impact from Zero Trust initiatives tailored to cloud environments:
Exposure Metrics
Percentage reduction in over-entitled user permissions and roles, orphan or unused resources, and policy exemptions granted
Access Efficiency
Decrease in access policy administration time through centralized identity and lifecycle automation
Policy Non-Compliance
Lower rates of cloud resource configurations and user activities defying security policies
Threat Containment Effectiveness
Faster isolation of compromised cloud functions and instances preventing lateral adversary movement
Mean-Time-To-Recover
Reduced time to restore operations by precisely scoping and remediating incidents in cloud environments
As these key performance indicators demonstrate, thoughtfully connecting Zero Trust programmes to quantified business risk reduction and improved security outcomes is critical to funding cloud maturity.
Conclusion
Legacy notions of network trust dissolved as assets distributed across scalable public cloud platforms, rendering perimeter-focused controls obsolete. By following Zero Trust precepts purpose-built for the cloud like unified visibility and control fabrics, least privilege access, and adaptive enforcement, organizations can meaningfully raise security and compliance confidence even as environments scale and threats accelerate.
