%20Icon.svg){kind=small}
Cloud applications make work more efficient. But they create security blind spots. Employees access cloud services from various devices and locations, often outside the reach of traditional security measures.
Cloud access security brokers (CASBs) fill this gap by providing visibility, control, and protection over cloud-based data and applications. Here’s how CASBs work, their key benefits, and how they help you enforce security without slowing down operations.
What Is a Cloud Access Security Broker?
As businesses rely more on cloud applications, traditional security tools struggle to keep up. A CASB is a security checkpoint between users and cloud apps, enhancing visibility, control, and protection as data moves between devices and endpoints.
CASBs provide multiple deployment options, depending on your organization’s security needs. For example, API-based CASBs integrate directly with cloud applications, offering deep visibility and data protection for sanctioned services. But they don’t inspect real-time traffic. Forward proxy CASBs act as intermediaries between users and cloud applications, enforcing policies in real time, though they’re often limited to managed devices. Reverse proxy CASBs provide security on managed and unmanaged devices by redirecting user traffic and ensuring real-time monitoring of sanctioned services.
For maximum flexibility, many organizations use multimode CASB solutions, which combine API, forward proxy, and reverse proxy capabilities to deliver comprehensive protection across all cloud environments. These CASBs detect shadow IT, enforce compliance with regulations like the Health Insurance Portability and Accountability Act (HIPAA) and General Data Protection Regulation (GDPR), and safeguard data using cloud access security broker tools. By integrating with code to cloud security solutions, CASBs work alongside emerging trends in cloud application security, protecting cloud environments without slowing down productivity.
Benefits of Cloud Access Security Brokers
Your organization faces evolving cloud security threats. CASB in cybersecurity mitigates these risks by securing SaaS, IaaS, and other cloud platforms, keeping data safe and preventing breaches. Here’s how:
Better Visibility Into Cloud Risks
A CASB gives you an in-depth view of how users interact with cloud applications, identifying unauthorized access and risky user behavior before it compromises your data. By continuously monitoring cloud traffic, CASBs offer the insights you need to enforce security policies and control sensitive data across managed and unmanaged devices.
Stronger Data Protection and Compliance
Cloud applications store massive amounts of sensitive data, and traditional security tools like firewalls and endpoint solutions aren’t always designed to enforce security policies in these environments. CASBs enforce encryption and apply data loss prevention (DLP) policies to protect sensitive data. They also work alongside cloud security posture management (CSPM) tools to maintain compliance with industry regulations.
Control Over Shadow IT
Employees may use unsanctioned cloud applications without IT’s approval, which introduces unknown risks. A CASB detects shadow IT, assesses the risk of unapproved applications, and blocks unsafe access if necessary. This allows you to regain control over cloud usage while giving employees the flexibility to use cloud services securely.
Advanced Threat Protection
Cloud environments are prime targets for phishing, malware, and account takeovers. CASBs employ user and entity behavior analytics (UEBA) to detect anomalies and prevent unauthorized access attempts. These solutions work alongside secure web gateways and firewall protections to continuously monitor cloud traffic for threats. Additionally, CASBs work in conjunction with application security posture management (ASPM) tools to remediate security gaps and enforce stronger cloud security policies.
4 Pillars of Cloud Access Security Brokers
A CASB’s four core pillars—visibility, data security, threat protection, and compliance—work together to protect sensitive information while maintaining operational efficiency.
1. Visibility
You can’t protect what you can’t see. A CASB provides real-time visibility into how cloud applications are used—not just what’s officially approved. Instead of only detecting unsanctioned apps or systems, it analyzes usage patterns, identifies risky behaviors, and helps you make informed decisions.
2. Data Security
Unlike on-prem environments, cloud applications don’t come with built-in security guardrails. CASBs extend security policies to cloud environments, enforcing encryption and DLP measures. These policies can apply to data at rest, in transit, and in use, protecting even downloaded files.
3. Threat Protection
Phishing, malware, and account takeover attacks no longer just target endpoints. They can happen inside cloud applications. CASBs go beyond basic threat detection by analyzing behavior across multiple cloud environments, flagging anomalies, and blocking unauthorized API connections or suspicious login attempts.
4. Compliance
With data constantly moving between cloud services, staying compliant is a challenge. Instead of relying on manual checks, a CASB monitors compliance in real time, flagging potential violations before they become an issue. This allows you to maintain regulatory requirements like HIPAA, GDPR, and the Payment Card Industry Data Security Standard (PCI DSS), as well as financial sector regulations such as the Sarbanes-Oxley Act (SOX) and the Financial Industry Regulatory Authority (FINRA) rules.
How Do Cloud Access Security Brokers Work?
A CASB secures cloud environments in three key stages: discovery, classification, and remediation. These steps give you full visibility into cloud activity and stop security threats before they escalate.
1. Discovery
CASBs begin by automatically detecting all cloud services, sanctioned and unsanctioned. This process, called shadow IT discovery, maps out the entire cloud landscape. Unlike traditional security tools, cloud security brokers provide deeper insight into cloud activity, ensuring that even hidden or unapproved applications are accounted for.
2. Classification
After mapping cloud activity, the CASB categorizes applications, users, and data based on security and compliance risks. It evaluates:
- Who is accessing cloud services?
- What type of data is being shared?
- How sensitive is the information?
CASBs enforce DLP policies, encryption, and access controls based on these factors. You can then define policies that restrict unauthorized file sharing, enforce multi-factor authentication, or block risky applications before they create security gaps.
3. Remediation
With discovery and classification in place, CASBs automate security enforcement. They can restrict access, encrypt data, or alert your security team if they detect a security risk, like a compromised account or unauthorized API connection.
How to Choose a Cloud Access Security Broker Solution: Factors to Consider
Not all CASB solutions are built the same. To align your security needs with the right tool, consider the following factors:
- Comprehensive visibility across cloud applications: An effective CASB monitors all cloud applications, allowing you to monitor user activity, track sensitive data movement, and identify high-risk applications before they become problematic.
- Advanced access and entitlement management: CASBs must let security teams track access at a granular level. It should support role-based access control (RBAC), multi-factor authentication (MFA), and conditional access policies to make sure only authorized users can interact with critical cloud applications.
- Automated threat detection and response: You can’t afford to track every alert manually. The best CASBs use AI-driven analytics and machine learning to detect anomalies and respond to threats in real time.
- Data loss prevention and encryption: CASBs should extend security policies to protect data both in transit and at rest. Look for built-in DLP capabilities to identify sensitive data, enforce encryption policies, and prevent unauthorized sharing or exfiltration.
- Seamless integration with existing security stack: A CASB shouldn’t operate in isolation. Integration with security tools like security information and event management (SIEM) and identity and access management (IAM) solutions create a unified approach to cloud security without unnecessary complexity.
Complement Cloud Access Security Broker Solutions With Legit Security
CASBs protect cloud applications by enforcing security policies, controlling access, and protecting data—but they don’t secure the underlying application code or software supply chain. That’s where Legit Security comes in.
With Legit, you can detect vulnerabilities in software components, ensure code integrity, and protect applications against threats introduced during development and deployment. Legit strengthens application security by securing the software supply chain, reducing risk before applications ever reach production.
Provide end-to-end cloud security from code to cloud. Book a demo of Legit Security today.