Home > Glossary > CompTIA Cybersecurity Analyst+ > Cloud Access Security Broker (CASB)

📖 What is Cloud Access Security Broker (CASB)?

A Cloud Access Security Broker (CASB) is a software tool or service that sits between cloud service consumers and cloud service providers. It enforces security, compliance, and governance policies for cloud-based resources, providing visibility into 'shadow IT' and data movement.

🥋 Sensei Says:

"Focus on the 'visibility' aspect. CASBs are essential for detecting unauthorized cloud application usage and ensuring data encryption across multi-cloud environments."

📚 Certification: CompTIA Cybersecurity Analyst+ (CS0-003)

🔑 What are the Key Concepts of Cloud Access Security Broker (CASB)?

  • Shadow IT Discovery: CASBs identify unauthorized cloud applications used by employees, enabling security teams to assess risk and bring these services under official corporate governance.
  • Data Loss Prevention (DLP): They monitor data in transit and at rest within cloud apps to prevent sensitive information from being leaked or shared publicly.
  • Deployment Modes: CASBs can operate via API for deep scanning of data at rest or as a proxy for real-time traffic control and policy enforcement.
  • Compliance and Governance: They ensure cloud usage adheres to regulatory standards like GDPR or HIPAA by enforcing encryption and access control policies across multi-cloud environments.
  • Threat Protection: CASBs detect anomalous user behavior, such as impossible travel or bulk data downloads, to identify compromised accounts or insider threats in the cloud.

🎯 How does Cloud Access Security Broker (CASB) appear on the CS0-003 Exam?

A scenario might describe a company discovering that employees are using unauthorized third-party storage apps to move corporate data. You will be asked to identify a CASB as the tool for detecting this shadow IT.

You may be asked to select the best solution for enforcing real-time data encryption and preventing PII from being uploaded to a SaaS platform, requiring a proxy-based CASB implementation.

Expect questions where you must distinguish between an API-based CASB for auditing data at rest and a proxy-based CASB for active traffic interception, specifically when deciding between retroactive scanning and real-time blocking.

❓ Frequently Asked Questions

How does a CASB differ from a Secure Web Gateway (SWG)?

While an SWG focuses on filtering web traffic and blocking malicious URLs, a CASB provides deeper visibility into cloud-specific API calls and data movements within SaaS, PaaS, and IaaS environments.


When should I choose API-based deployment over Proxy-based deployment?

Choose API-based for deep scanning of data at rest and auditing without impacting user performance. Use Proxy-based when you need real-time control, such as blocking specific actions or encrypting data in transit.

Related Terms from CompTIA Cybersecurity Analyst+

📝 Related Study Guides

Comparison 8 min read

CISSP vs CISM: Which Certification Should You Pursue in 2026?

Choose CISSP if you want broad technical security expertise across eight domains, including cryptography, network security, and software development. Choose CISM if you're focused on information security management, governance, and risk management from a leadership perspective. CISSP is ideal for hands-on security architects, while CISM is designed for security managers and directors.

Career Guide 9 min read

The IT Certification Roadmap: Where to Start in 2026

Start your IT certification journey in 2026 with CompTIA A+ for general IT foundations, then branch into networking (Network+), cybersecurity (Security+), or cloud computing (AWS Cloud Practitioner or Azure Fundamentals) based on your career goals. Each path leads to advanced certifications like CISSP, AWS Solutions Architect, or CISM within 2-3 years of focused progression.

Comparison 10 min read

CISSP vs CISM: Which Certification Should You Pursue in 2026?

The CISSP is a broad, technical-to-managerial certification focusing on security operations and architecture across eight domains. In contrast, CISM is a specialized management certification centered on governance, risk management, and program development. Choose CISSP for comprehensive security expertise and CISM if you are pivoting specifically into security leadership and governance roles.

🧠

Test Your Knowledge

Think you understand Cloud Access Security Broker (CASB)? Put it to the test with our practice exam.

Try 10 Free Questions

⭐ 1,000 expert-curated questions available with Premium

Upgrade Premium