This is part of a series of articles about Cloud Security-ST
What Is SaaS Security?
Software as a Service (SaaS) is a software delivery model in which cloud providers host applications and make them available to end users over the Internet. It is common for independent software vendors (ISVs) to contract with a third-party cloud provider to host their applications. In some cases, the cloud provider is also the software vendor.
SaaS security, a subset of cloud security, is a set of practices and tools designed to protect Software-as-a-Service (SaaS) applications and the sensitive data they hold. It involves establishing strong access controls and secure configuration for SaaS applications, ensuring least privilege access, and protecting data via encryption or other methods.
SaaS security is not the sole responsibility of organizations using cloud services—SaaS is based on a shared responsibility model. The SaaS provider is typically responsible for securing their systems and infrastructure (including any aspect not directly managed by the customer), and provides security features that customers can use to secure their applications and data. It is the SaaS customer’s responsibility to correctly set these configurations to ensure SaaS applications are secure.
Related content: Read our guide to cloud security compliance.
In this article:
7 SaaS Security Risks and Concerns
Although SaaS applications have unique security concerns, keep in mind that all SaaS applications are also web applications. This means they are susceptible to all common web application vulnerabilities, including the OWASP Top 10.
Some of the severe threats facing SaaS applications include:
- Security misconfiguration—SaaS software may provide security controls, but very often these controls are not defined correctly or at all. One administrator error or omission can expose highly sensitive data and business functions to the public Internet.
- Cross-Site Scripting (XSS)—a common web application vulnerability, which allows attackers to inject malicious code into a page displayed by the end user. Newer versions of web application frameworks can prevent this vulnerability.
- Insider threats—deliberate data breaches by employees or trusted third parties can also pose a security risk to SaaS applications. Many organizations do not enforce least privileged access, meaning that a malicious insider can gain access to many application functions they do not actually need, or even to the entire application.
- API security—SaaS applications usually have their own APIs for interacting with existing resources to provide core functionality. However, this API can be a cybersecurity threat. APIs are easy targets for attackers due to data breaches, authentication issues, and mass deployment without fine-grained controls.
- Personal information—many SaaS applications hold personally identifiable information (PII) or financial information belonging to end-users or customers of the organization using the application. A breach of the SaaS application can lead to exposure of this sensitive data, with serious compliance and legal consequences.
- Account hijacking—account hijacking is a major threat when organizations migrate services to SaaS applications and allow users to work remotely. Attackers can use social engineering, and take advantage of unsecured personal devices, to compromise user accounts and move laterally through the SaaS environment.
- Compliance requirements—most industries have compliance requirements and security audit procedures (a few examples are GDPR for data protection, HIPAA for healthcare, PCI DSS for retail online payments, and SOX for finance). Organizations covered by regulations and compliance standards should prioritize protecting sensitive data, frequently monitor user activity through logs, and ensure they have a full audit trail for all relevant SaaS applications.
SaaS Security Best Practices
Strong Authentication
Authentication mechanisms help ensure only authorized users can access SaaS resources. However, each SaaS provider offers different authentication options. It is critical to investigate how the vendor handles authentication before committing to the service.
Some cloud providers allow integration with identity providers, such as Azure Active Directory (AD) using Security Assertion Markup Language, OpenID Connect, or Open Authorization. Some providers offer multi-factor authentication (MFA), and if so, it must be enabled to reduce the chance of account compromise.
Learn more in our detailed guide to cloud security best practices.
Data Encryption
Data encryption is a standard mechanism for protecting information. Most SaaS applications use TLS to encrypt data in transit, and most providers offer an additional encryption mechanism for data at rest. Some SaaS providers offer encryption as a default feature, while others require customers to explicitly enable this functionality.
Discovery and Inventory
The SaaS model enables you to deploy applications quickly. It offers great scalability but also may expose you to risks. Monitoring unexpected usage can help manage this risk, using manual data gathering and automated tools to monitor usage and maintain a reliable services inventory. Ideally, your inventory should help learn who uses which service across the entire organization.
Consider CASBs and SSPM
Cloud access security brokers (CASB) enable you to add a layer of security controls that extends the SaaS provider’s built-in offerings. It helps extend your visibility and control beyond the scope offered by your SaaS provider. CASB services offer various deployment modes, such as proxy or APIs, allowing you to choose the option that suits your architecture.
SaaS security posture management (SSPM) solutions provide automation and security capabilities that extend visibility into the security posture of a SaaS environment. These solutions help remediate security concerns in SaaS environments more easily. Here are key SaaS security aspects covered by SSPM solutions:
- Security controls—SSPM solutions help review existing controls implemented to protect SaaS applications against internal and external cyberattacks.
- Security management—SSPM solutions provide techniques and tools to help implement, optimize, and update security policies.
- Detection and response—SSPM solutions can detect threats, mitigate security incidents, and recover from cyberattacks.