What Is a Cloud Access Security Broker and Does Your Business Still Need a CASB?
September 29, 2026
Cloud applications have become part of everyday business operations, giving employees access to applications, files, and business data from offices, homes, and other locations. This flexibility also changes how organizations need to approach security. Traditional network controls may provide limited visibility into activity taking place within cloud applications, particularly when users access services outside the corporate network.
A Cloud Access Security Broker, or CASB, addresses this challenge by providing visibility and security controls between an organization's users and the cloud services they access. For businesses managing sensitive information across multiple cloud applications, understanding what a CASB does and where it fits into the security environment is an important part of evaluating cloud security requirements.
A Cloud Access Security Broker is a security technology designed to provide greater visibility and control over cloud service usage. NIST recognizes CASB as a cloud security technology used to monitor activity and enforce security policies as cloud resources are accessed. A CASB can monitor cloud activity, enforce security policies, protect sensitive data, and help identify potentially risky activity. The capabilities available depend on the specific product, its deployment model, and the cloud services it supports.
One of the primary functions of CASB is providing visibility into cloud application usage. Employees may use approved business applications alongside services that have not gone through an organization's security review. Without sufficient visibility, security teams may have difficulty identifying which cloud services are being accessed, who is using them, and how business information is moving through them.
This visibility is particularly useful when an organization relies on numerous SaaS applications. Different departments may adopt different services for collaboration, file storage, project management, customer management, and other business functions. Managing security policies across these applications can become difficult when each service has different administrative controls and security capabilities. CASB can provide a more centralized approach to monitoring and governing supported cloud services.
Data protection is another core function. Cloud applications can contain customer information, financial records, intellectual property, employee data, and other sensitive material. A CASB can apply policies governing how sensitive information is accessed, shared, uploaded, or transferred through supported cloud services. Depending on the platform, these controls may include data loss prevention, access controls, classification, encryption-related capabilities, and activity monitoring.
Data loss prevention becomes particularly relevant when employees can easily share information through cloud applications. For example, an organization may prohibit sensitive files from being uploaded to an unauthorized cloud service or shared with an external account. A CASB can identify activity that conflicts with configured policies and respond according to the organization's requirements. Depending on the solution, that response may involve blocking an action, generating an alert, or applying another security control.
CASB can also contribute to cloud threat protection. Cloud accounts can be targeted through stolen credentials, compromised sessions, malicious applications, and other forms of unauthorized activity. Monitoring cloud activity gives security teams additional information for identifying behavior that may indicate a security issue.
These capabilities do not replace identity security, endpoint protection, network security, or incident response. CASB addresses security concerns associated with cloud services and works alongside other controls as part of a broader cybersecurity architecture.
CASB can also support compliance efforts by providing controls and activity information related to cloud applications. Organizations may need to demonstrate that sensitive information is protected and access is appropriately controlled. A CASB can contribute through monitoring, policy enforcement, and data protection capabilities, but it does not make an organization compliant by itself. Compliance depends on the organization's complete security program and the requirements that apply to its operations.
CASB remains relevant for organizations that need greater control over cloud applications, but the need for a particular solution depends on the organization's environment. The decision should begin with the security problems the business needs to address rather than the technology itself.
An organization may have strong endpoint protection and identity controls while having limited visibility into cloud application activity. Another may have sensitive information spread across numerous SaaS platforms and need more consistent policies for controlling access and data sharing. Some businesses may already have CASB capabilities incorporated into a broader security platform.
The scale and complexity of cloud usage are also important considerations. As organizations adopt more cloud services, security teams need reliable ways to identify applications, monitor activity, and enforce appropriate policies.
CASB can also help address shadow IT. Employees may adopt cloud applications without going through an organization's security or IT review process. These services can introduce risks if sensitive information is stored or shared without appropriate controls. CASB technology can provide visibility into cloud services being used across an organization, allowing security teams to identify applications that require review and determine how they should be governed.
Existing security architecture should also be considered. Organizations may already have tools for identity management, data loss prevention, endpoint protection, security information and event management, and other security functions. A CASB should complement these controls rather than create unnecessary overlap.
For some organizations, CASB functionality may already be incorporated into a broader security platform. Rather than focusing exclusively on standalone CASB products, security teams should examine the cloud security capabilities available within their current environment and identify remaining gaps.
The more useful question, therefore, is not simply whether businesses still need CASB. It is whether an organization has cloud security requirements that CASB capabilities can address. Cloud application visibility, data protection, threat detection, shadow IT discovery, and policy enforcement are all areas where CASB can provide useful security controls.
Implementing CASB requires a clear understanding of the organization's cloud environment. Security teams should establish which cloud applications are being used, what information those applications contain, how users access them, and which security controls are already in place.
Integration is another important consideration. A CASB may need to work with identity systems, cloud applications, security monitoring platforms, data protection technologies, and other security controls. Organizations should evaluate how the solution collects activity data, applies policies, generates alerts, and shares security information with other systems.
Supported cloud applications also matter. CASB capabilities vary between vendors, and not every solution provides the same level of visibility or control across every cloud service. Organizations should evaluate the applications they rely on most and confirm that a prospective solution provides the necessary capabilities.
Policy design is equally important. Security teams need to define what activity is permitted, what information requires additional protection, and what actions should generate alerts or enforcement. Without clear policies, a CASB can produce large amounts of security information without giving teams meaningful direction.
Organizations should also consider how alerts will be handled. Detection is useful only when security teams have processes for reviewing relevant activity and responding to legitimate security events. Integrating CASB information with existing monitoring and incident response processes can help reduce fragmented security operations.
A CASB should ultimately have a defined role within the broader cybersecurity architecture. It can provide cloud visibility, data protection, threat detection, and policy enforcement, but it does not replace the other controls required to secure an organization's technology environment.
For organizations using multiple cloud applications, CASB can provide a practical way to gain greater visibility and control over cloud activity. Businesses evaluating CASB should focus on their actual cloud usage, existing security controls, sensitive information, and policy requirements before deciding how the technology should be implemented.
If your organization needs help assessing its cloud security requirements or determining how a Cloud Access Security Broker can strengthen visibility, data protection, and policy enforcement, contact Alacrinet to discuss your environment and identify the CASB capabilities that fit your security needs.
