Everything You Need to Know on CASB

The structure of CASBs is built on four pillars: visibility, data security, compliance, and threat protection. The pillars are essential to the functionality of a CASB and business use cases.

The visibility pillar offers administrators insight into cloud apps, data access, and storage. It detects misconfigured cloud resources and protects against data leaks.


With cloud adoption accelerating, enterprises are exposed to new risks. Employees may share sensitive information outside approved systems — for example, engineering designs or customer sales records shared via cloud-based messaging tools or collaboration platforms. This unsanctioned use of cloud applications and services is called shadow IT and can be dangerous. CASBs can help prevent data breaches and improve visibility into the cloud environment by enforcing security policies that can block or alert on activities that don’t comply with an organization’s security standards.

In addition to granular data access controls, CASBs can safeguard IaaS and SaaS environments with features like activity monitoring, threat detection and mitigation, and account management. These features of CASB explained to extend the capabilities of on-premises data loss prevention (DLP) solutions, which typically do not protect data traveling between the enterprise and third parties.

CASBs can also mitigate security risks by encrypting or tokenizing data destined for the cloud. However, this type of protection is typically bundled with other CASB functions because cryptography requires substantial subject matter expertise that may be outside the vendor’s technology offerings. For instance, many CASBs offer secure web gateway capabilities; some even bundle SD-WAN with a full suite of network security services. This simplifies deployment and reduces the number of vendors a security team must work with.


The area at the network edge between an organization’s corporate network and third-party cloud applications is a prime target for attackers looking to breach and exploit. The CASB bridges this gap by identifying and assessing risk at the business level, protecting data and users.

Visibility allows administrators to monitor unauthorized devices, such as shadow IT, and identify potential security vulnerabilities. It also helps detect suspicious activity, such as unauthorized file uploads to unintended locations, and alerts administrators. It also discovers unsanctioned SaaS apps and enables administrators to apply appropriate access controls.

Granular cloud usage control ensures that only authorized users can access sensitive information stored in the cloud. This can be achieved through inline and out-of-band inspection of cloud web traffic, enabling businesses to align policies with data security requirements and help meet regulatory compliance standards such as GDPR.

Threat protection defends against modern threats, including ransomware and other malware, targeted at SaaS applications. This includes the detection of malicious domains, URLs, and IP addresses; static and dynamic malware detection; and advanced machine learning to spot emerging threats.

CASB can be delivered as on-premise hardware or software but is best as a cloud service to simplify management and scalability. It can be deployed via proxying (forward or reverse), APIs, or both (also known as multimode). When selecting a CASB, look for a vendor with multiple architecture options to ensure it covers all your needs, including those for hybrid environments.


As organizations migrate to the cloud, they must comply with a myriad of regulatory standards. These regulations often require strict data protection rules that can be difficult to implement and enforce, primarily when the organization is based in multiple locations and has remote workers. CASBs can help IT teams meet these compliance requirements by monitoring the entire cloud infrastructure, discovering all applications and devices in use, detecting and stopping unauthorized activity, and enforcing data-centric policies.

With the rise of bring-your-own-device (BYOD) programs and unsanctioned employee app usage (shadow IT), CASBs provide visibility into and control over third-party applications that may be in use. Rather than banning these tools or disrupting productivity, a CASB provides a granular approach to data protection and policy enforcement – making it safe for employees to utilize time-saving, productivity-enhancing cloud services.

CASBs also guard against threats with security capabilities like malware prevention, sandboxing, dynamic and static anti-malware detections, threat intelligence sources, machine learning and ransomware detection, and data loss prevention. This is in addition to cloud context and activity monitoring, discovery, classification, and remediation of SaaS and IaaS environments.


With CASB, enterprises gain visibility into and control over their cloud app usage and sensitive data. A CASB also helps organizations reduce the risk of shadow IT, which occurs when employees deploy applications and infrastructure outside the IT department’s oversight. Such applications and unauthorized assets risk the environment because they are frequently unsecure, relying on default passwords or configurations that attackers can compromise. A CASB solution can identify such assets and provide a way to remediate them automatically.

CASB solutions can help IT departments gain more insight into the applications being used, which enables them to more effectively shape access policy based on the use case and device type of the employee in question. Unlike traditional binary security systems that only block or allow access, CASBs perform risk assessments of all cloud apps and services users use, both within and outside the enterprise.

A CASB can also safeguard sensitive data by encrypting files stored in or transmitted over the network, helping to protect against malware and data theft. In addition to securing data-at-rest, a CASB can monitor and control data-in-motion by leveraging advanced security features like credential mapping and single sign-on (SSO), logging, alerting, and device posture profiling. CASBs can be deployed in proxy mode, which intercepts requests for cloud services and enforces policies inline, or via API integrations, which focuses on monitoring and controlling SaaS and IaaS through their application programming interfaces (APIs).