What is cloud security?

Modern cloud environments scale, shift and evolve quickly. As a result, legacy security frameworks, like those you use for your traditional on-prem assets and infrastructure, can’t keep up. When you try to use those outdated resources in cloud environments, you create security blind spots that actually increase your cloud risk — not reduce it.

That’s why cloud security isn’t just a set of tools or best practices — it’s a mindset. It’s a more modern approach to secure cloud-native infrastructure, data, identities and applications in real time.

As your organization adopts multi-cloud and hybrid cloud strategies, traditional perimeter-based security models won’t work. You can’t secure a boundary that doesn’t exist. Cloud security gives you the visibility and control you need to manage dynamic risk — without slowing your teams or sacrificing the benefits of agility, scalability and innovation.

Cloud security uses tools and resources designed to protect cloud-based infrastructure, apps, workloads and data.

It includes everything from access control and encryption to vulnerability management, data loss prevention and compliance.

Cloud security is more than just a bunch of security controls. It’s a continuous process that monitors and adapts to threats in cloud environments that change minute by minute.

Unfortunately, even with its business benefits, the cloud introduces new risks you can’t overlook.

According to Tenable’s Cloud Risk Report, 38% of organizations have publicly open cloud tasks that are critically weak and have high-level privileges. This “toxic cloud triad” increases risk of data breaches.

And, if you’re still using traditional vulnerability management tools that don’t work in dynamic cloud environments, you may never know you have these issues.

Cloud security works differently than traditional IT. It’s all about shared responsibility between you and your cloud provider. That responsibility shifts based on whether you’re using SaaS, PaaS or IaaS. Responsibilities change with each service type.

For your responsibilities, your cloud security tools should empower you to continuously and automatically monitor everything you’re running in the cloud — all your assets, user accounts and workloads as they spin up, not days later when you run a static scan.

You should also be able to spot cloud security threats before they become breaches, like misconfigurations, vulnerabilities, users with too many permissions or other suspicious activities.

Your goal is to expose and fix these security gaps before threat actors take advantage of them.

Your cloud security measures should also make sense for your business. They should match your goals, your organization’s risk appetite and compliance requirements.

Quite simply, your cloud security policies should support fast movement in the cloud, but do so smartly.

That means shifting to new ways of thinking about cloud infrastructure and identity management, which you can’t approach as you do with traditional on-prem security.

Containers, serverless functions, ephemeral compute instances and APIs all expand your attack surface. Multi-cloud and hybrid cloud security add complexity. Your cloud security program has to consider this and be able to instantly and automatically respond.

It’s important to understand that no two cloud environments are alike. The controls you apply in a DevOps-heavy AWS environment might look very different from those in a compliance-focused Azure tenant. Your cloud security tooling must keep up with all of it.

Cloud-native security architectures, like cloud-native application protection platforms (CNAPPs), are helpful here. CNAPPs give you a contextual understanding of how your cloud exposures stack up, where you have the greatest cloud risk, and how to quickly take action to reduce risk. It helps you go beyond fixing an ever-growing list of vulnerabilities just because an arbitrary vulnerability scoring system told you to.

Continuous risk management is the heart of cloud security. It ensures you use the most effective safeguards at each cloud layer alongside automated systems that adapt when your environment changes.

In terms of how cloud security works, it’s more than just managing who can access what in the cloud. It goes deeper than assigning roles. You need to see the full picture:

• What data are people accessing?
• How frequently are they doing it?
• Where are they connecting from?
• Why do they need access?
• How long do they need access?

To do this most effectively, you should use just-in-time (JIT) access, least privilege enforcement, zero trust and real-time entitlement reviews.

It’s also important to remember that your sensitive cloud data doesn’t just live in databases. It flows between services, containers, functions and SaaS apps. You need encryption at rest and in transit and policy controls to stop data leaks. Data security posture management (DSPM), for example, gives you insight into where your sensitive data is and if you’ve properly secured it.

Although the cloud helps you scale, it also multiplies misconfigurations. However, you can use policy-as-code, infrastructure-as-code (IaC) scanning and security posture management tools to proactively catch drift, flag risky defaults and enforce guardrails.

Today’s cloud environments have evolved well beyond virtual machines (VMs). Now, you’ve got Kubernetes and containers, Lambda functions and more. You have to protect all of them.

These resources spin up fast, work briefly, and then disappear. That’s why traditional vulnerability scanning doesn’t work. Instead, you need agentless runtime monitoring to get holistic visibility into your workloads as they move through development, testing and production.

Real-time monitoring is important here. But you need to consider more than logs. You must also monitor APIs and behavior baselines to spot suspicious behaviors. Orchestration with system information and event management (SIEM) and security, orchestration and response (SOAR) systems, and detection pipelines ensure the right teams can respond quickly to limit breach impact and speed up response and recovery.

Your cloud security tools should prioritize risks based on context (business impact, exposure, exploitability and asset criticality), route them into your workflows (like Jira or ServiceNow) and validate that your fixes actually work.

Cloud security is vastly different from traditional cybersecurity.

Legacy systems use clearly defined boundaries like a trusted network perimeter, static assets and direct control over physical hardware.

In the cloud, those boundaries don’t exist. Your cloud workloads are highly distributed, your environments dynamically scale, and data constantly moves across APIs, platforms and beyond. Network perimeters are obsolete.

The core difference between traditional and cloud security?

Cloud security is identity-centric, policy-driven and behavior-aware.

You can still use familiar tools like encryption, segmentation and firewalls, but they work differently in the cloud. Cloud firewalls, for example, are virtual. Access control policies integrate with identity providers. Audit logs live in your cloud-native SIEM, not an on-prem Syslog server.

The benefit? When done right, cloud security uses faster detection, smarter remediation and more granular visibility than traditional cybersecurity practices.

Your cloud infrastructure contains vast amounts of sensitive information, such as customer and financial data, proprietary code and business-critical services. This makes it a top target for cyber attackers.

But it’s not just attackers that want access. Other people, like your auditors, regulators and partners, have their hands in your cloud. Plus, your customers expect you to keep their data safe.

As cloud adoption accelerates, so does your risk. Without proper controls, cloud systems and services introduce vulnerabilities, often through simple and unintentional misconfigurations.

You can run into some real headaches when you don’t build security into your cloud from the start. Those S3 buckets your team didn’t set up properly? They can leak sensitive data. And, when people have more access than they need, attackers can use that to move laterally through your systems.

The worst part is your teams often scramble to figure out who has access to what and fix configuration drift in the middle of a breach. They constantly play catch-up and never get a chance to look ahead to proactively prevent attacks before they happen.

Cloud security is about being resilient. Regulations like GDPR, HIPAA and PCI DSS require you to actively manage risk — and you’ve got to prove to them you’re doing what you say you are.

That’s exactly what good cloud security hygiene does. And, it can help your developers work faster with fewer security fears holding them back.

Resilient organizations understand cloud security isn’t an IT issue alone; it’s a business issue. When done well, you can anticipate fewer breaches, and when you do have them, you can respond much faster.

When you can quantify risk exposure, prioritize and measure remediation progress and align cloud security metrics with your business priorities, you can build executive and board support and access funding for cloud resources to mature your cloud security program.

Your path to the cloud likely uses a mix of deployment models. Your cloud security principles should be consistent for each, but how you apply them depends on your cloud architecture.

Public cloud platforms like AWS, Azure and Google Cloud are shared environments. You don’t control the infrastructure, but you control how you configure and secure your workloads, users and data.

Simple mistakes, like accidentally over-permissioning a role, can have dire consequences.

Private cloud environments have a dedicated infrastructure and are often hosted on-prem or through a managed provider. You have more control, but also more responsibility for securing your full stack.

Hybrid cloud environments combine both. They’re ideal if you’re gradually moving workloads or keeping sensitive data in controlled environments while using the public cloud to scale.

Whichever model you use, your cloud security practices must flex around it. The best programs apply consistent principles like least privilege, strong identity controls and security posture management across all environments, even if your tools vary.

Cloud environments give you more speed and the ability to scale, but managing cloud security is complex and comes with risk.

Here’s where many organizations struggle:

• Incomplete visibility into all cloud assets. Shadow IT, unmanaged identities and short-lived assets often go unnoticed. If you can’t see those assets, you can’t secure them.
• Overprivileged accounts, stale access tokens and poor role-based access controls (RBAC) can allow attackers to compromise the cloud for weeks, months or longer, often without your knowledge.
• Misconfigurations are common: an open port here, a default password there and a public-facing admin panel. Individually, they’re risks. Together, they’re potential breaches.
• Without security built into your development lifecycle, vulnerabilities move into production unnoticed. Compliance checks are painful and remediation takes longer than it should.
• Attackers don’t need complex attack vectors. They just need to string together whatever you missed. A container with critical vulnerabilities, a hardcoded key and a lack of logging create toxic combinations and attackers know how to find them.

Each cloud security layer you implement adds coverage, context and control to reduce cloud exposures and make your environment harder to compromise.

• Establish security guardrails from the top down. Frameworks like NIST, ISO 27001 and CIS Benchmarks are a starting point. Use policy-as-code to enforce them across teams and pipelines.
• Protect your network and control traffic in and out of your environment. Virtual private clouds, subnets, firewall rules and segmentation reduce lateral movement and isolate risk.
• In the cloud, your identities are your perimeter. Apply least privilege, remove unused access and enforce just-in-time access for sensitive roles.
• Monitor your virtual machines, containers, serverless functions and short-lived resources. You need visibility into every layer.
• Protect your sensitive information with encryption.
• Use DSPM for cloud data visibility and protection.

Automate manual tasks and evidence gathering for compliance and audits.

Point solutions create cloud visibility gaps, which increase your risk when you’re trying to decrease it. Instead, look for cloud security software that integrates multiple cloud tools into a single platform.

The cloud security tools should support:

• Agentless assessment to continuously discover and monitor cloud assets without friction or performance issues.
• IaC scanning to find misconfigurations before your teams deploy them. Adopt a shift left strategy to reduce risk early.
• Cloud identity and entitlements management (CIEM) to find and manage permissions across users, roles and services. Your cloud tools should be able to automatically address overprivileged access and dormant entitlements.
• The ability to replace standing privileges with temporary access that disappears after use.
• Automated remediation to route prioritized risks into existing workflows like Jira, ServiceNow and CI/CD so your teams can act fast.
• Contextual risk scoring to focus on which security vulnerabilities may have the greatest impact on your organization. Do more than just listing vulnerabilities. Rank them based on attack paths, business impact and likelihood an attacker may exploit them in the near term.
• Broad support across cloud providers like AWS, Azure, GCP and Kubernetes without blind spots.

Choosing the right cloud security platform is all about fit for your environment, workflows and business goals.

Ask the cloud security vendor:

• Does the solution have real-time visibility across all cloud assets, services and identities?
• Can it prioritize risks based on real-world context, not just CVEs or CVSS?
• Does it support the full CNAPP model—including CSPM, CIEM, DSPM and cloud workload protection (CWP)?
• Can we automate remediation and integrate findings into our CI/CD and ticketing tools?
• Does it align with our compliance frameworks and reporting needs?
• Is the interface intuitive for everyone to use?
• What’s not included?

It’s important to note some platforms charge extra for basic capabilities or they’re hard to set up and use. Others promise automation, but lack actionability.

Ultimately, the right cloud security system for your organization will reduce cloud complexities and help you confidently automate and manage your program.

Use frameworks like NIST as the foundation for your cloud security strategy.

Here’s how that maps to your environment:

1. Know

   Use cloud connectors to continuously map assets, accounts, services and configurations across all your public, private and hybrid cloud environments.

2. Expose

   Scan for misconfigurations, vulnerabilities and identity and access risks. Layer multiple sensors like agentless scans, API-based assessments and IaC analysis to get full context.

3. Prioritize

   Not all risks are equal. Prioritize risk remediation based on exploitability, sensitivity, lateral attack pathways and business impact. Use contextual risk scoring to understand which cloud security issues to address first.

4. Close

   Route findings into ticketing, CI/CD or bug-tracking tools. Assign owners, automate fixes where possible and shift remediation left by fixing IaC templates and base images.

5. Measure

   Track attack surface reduction, time to remediation and compliance. Set key performance indicators (KPIs) early and routinely share those metrics with your C-suite and board. This can help demonstrate security progress and align your security program with your organization’s guiding objectives.

Mature, high-performing cloud security programs enforce least privilege and zero trust across all cloud apps, systems and services.

Here are a few recommended best practices:

• Eliminate standing admin roles.
• Shift security left with IaC scanning and policy-as-code.
• Catch issues early; fix them fast.
• Implement JIT access for sensitive systems.
• Limit blast radius by reducing standing access.
• Continuously monitor for drift, risky behaviors and misconfigurations.
• Use automation for key processes like remediation, privilege and user management, reporting and alerts.
• Integrate security early into your software development lifecycle.
• Crosswalk controls to compliance frameworks.
• Proactively track and store evidence in a single source of truth.
• Make cloud security and awareness an organizational priority.
• Develop ongoing training and education.
• Involve key teams, like engineering, DevOps, IT and governance early. Work with them often.

1. Secure IaC by scanning Terraform or CloudFormation templates. Look for risky configurations. Address issues like open ports, weak encryption and hardcoded credentials before deployment.
2. Integrate security into your CI/CD pipeline using automated scans. Find and fix vulnerabilities, policy violations and configuration issues before production.
3. Protect runtime. After deployment, automatically and continuously monitor workloads. Use agentless tools to scan virtual machines, containers and serverless for misconfigurations and vulnerabilities.
4. Enforce least privilege. Use zero trust, JIT access and entitlement management to ensure users only have access to what they need when they need it, nothing more.
5. Automate fixes and feedback loops. Route findings into developer workflows. Fix issues in source code, like IaC templates and container images.

Report and improve on your cloud security metrics. Track, measure and share exposure metrics, including mean time to remediation (MTTR) and risk reduction trends with stakeholders. Demonstrate how cloud security improves operational resilience and supports velocity.

How are public and private cloud security different?

Public clouds share infrastructure but separate tenants. You’re responsible for securing workloads and data. The CSP secures infrastructure. Private clouds give you more control but also more operational and security responsibilities.

Is the cloud more secure than on-prem infrastructure?

It can be. Cloud providers invest heavily in security, but your configuration, access policies and monitoring determine how secure your environment really is.

What is a CNAPP?

A cloud-native application protection platform unites CSPM, CIEM, CWP, DSPM and other cloud tools into a single platform to secure cloud-native environments.

What’s JIT access?

Just-in-time access grants privileges only when needed and automatically revokes them.

How is cloud IAM different from traditional IAM?

Cloud identity and access management works for dynamic workloads, temporary identities and federated access. It must function in real time and scale across services and regions. Traditional IAM uses static roles and perimeter-based access.

What’s a toxic combination?

A toxic combination is when multiple small risks, like unpatched workloads, exposed credentials, misconfigurations and over-permissioned identities, combine and create a breach path.

How does Tenable help with cloud security?

Tenable Cloud Security includes agentless cloud scanning, CIEM, CSPM, DSPM, CWP, threat intelligence and AI-driven risk prioritization.