Why Are Third-Party SaaS Integrations a Threat?

Third-party SaaS integrations Are a Threat

Software as a Service (SaaS) platforms allow enterprises to outsource many of today’s administrative demands. A SaaS platform can provide customer relations tools for sales and marketing staff, tax tools for the financial team, and the very foundation of a development process. 

Now that AI tools have joined the fray, the sheer quantity of corporate information being handled by external companies and the processes by which that information is retrieved from internal networks represent a key threat to data security. 

Understanding the SaaS Attack Surface

SaaS is any software that is managed and delivered by an external organization: the organization pays on a per-usage basis through a software license, and in return, they’re granted access to the software. 

Because this software is managed remotely, all the organization needs is money, a compatible device, and an internet connection.

The Security Considerations

While SaaS offers convenience, it also raises significant security concerns:

  • Data Storage Risks. SaaS providers store, process, and sometimes analyze user data.
  • Limited User Control. Organizations relying on SaaS have no direct oversight of data processing mechanisms.
  • Regulatory Concerns. Compliance frameworks like GDPR distinguish between Data Controllers – Organizations that determine what customer and employee data is collected and Data Processors – SaaS providers that handle the collected data.
  • Data Collection by Providers. Many SaaS providers not only process but also collect customer data, increasing risk exposure.

Mitigating SaaS Security Risks

Due to the sensitive nature of SaaS data processing, organizations increasingly demand proof of strong security measures from their providers. One key certification is ISO 27001, which verifies that a SaaS provider’s security controls can identify and mitigate risks such as:

  • Unauthorized data access and breaches
  • Weak authentication and identity management
  • Data leakage through misconfigured cloud environments
  • Lack of encryption for stored and transmitted data

As businesses continue to integrate SaaS into their operations, understanding these risks and verifying a provider’s security posture is essential for protecting sensitive data and maintaining compliance.

Data Theft

Because SaaS providers store enterprise data on their servers, the data is subject to their own data protection controls. These controls are often too lax – so much so that entire Advanced Persistent Threat groups have earned reputations from stealing from SaaS providers’ databases. 

UNC3944 – also known as Scattered Spider – is one of these APTs. UNC3944 uses social engineering attacks, leveraged at SaaS providers’ help desks:

  • They sidestep authentication by posing as an employee
  • Re-using credentials from previous data breaches
  • Claiming to need MFA resets due to receiving new devices

This often proves enough to fool the SaaS provider’s systems into mistaking them for the real customer. 

They then test what protections the customer has placed around their SaaS environments, and start exfiltrating data from those left lacking. In earlier attacks, Scattered Spider used to deploy ransomware – they have since started skipping this and got straight to exfiltration. 

API Risk

Most SaaS providers boast the ability to simply plug-and-play – to easily and quickly begin moving data from an organization’s own network(s). This is facilitated by Application Programming Interfaces (APIs). To differentiate the forms that enterprise data can take, consider its two categories: 

  • Data in-motion
  • Data at-rest

The former describes how data is transmitted – which is where APIs come into play. Allowing different applications to share data often relies on the apps’ APIs – and when a user is authenticated on one application, it would be a significant drain to re-input login details every time an app accesses data from another app via its API. 

The answer is Oauth

Oauth allows an application to share an app’s credentials. However, if the API is not well protected, it’s possible for an attacker to intercept and steal the authentication token. This would allow an attacker to access the corresponding database, just as if they had stolen a username/password combo. 

And because these APIs are managed by the SaaS provider it can be difficult to determine their security from a client’s perspective. 

It’s not just data at rest that can be mishandled: whenever an API retrieves information from a database and delivers it to a destination service, gaps can arise. Broken object property-level authorization is a very common risk, and sees an API unwittingly ‘leak’ data about the organization’s underlying architecture.

AI Has Increased the Risk of Data Spillage

Training generative AI models involves exposing them to vast amounts of data, enabling them to identify patterns and trends relevant to their intended applications. For effective training, the data should accurately reflect the specific use cases the model is designed to support.

However, if the training data contains sensitive information, such as personally identifiable information (PII), the model may inadvertently retain and disclose this data in its outputs, exposing it to unauthorized users. 

Testing this is even harder – large language models (LLMs) can generate varying outputs for the same input, making them far less predictable than traditional software. While this fosters creativity and diverse content generation, it also makes testing for consistent outputs difficult.

 As a result, GenAI models can unintentionally leak sensitive information during outputs, compromising any confidential information they’re trained on. 

How to Secure Third-Party SaaS Integrations: 4 Effective Ways

A blanket ban of SaaS integration would risk compromising an organization’s innovation – and drastically increase the cost of development. 

To balance the risk against SaaS’ rewards, organizations need to secure the entire data pipeline. 

#1: Asset and API Discovery

The number of SaaS applications – and their corresponding variety of API plugins – make keeping track of every API’s permissions and data handling processes almost impossible. 

The answer to this is a security approach that discovers and tracks every asset and connected API, which involves:

  • Identifying all APIs – Including internally developed, third-party, and undocumented (shadow) APIs.
  • Mapping API interactions – Understanding how each API interacts with endpoints and applications.
  • Analyzing request methods – Tracking GET, POST, PUT, and DELETE operations.
  • Assessing authentication and authorization – Ensuring APIs use secure access controls.

Automated tools are able to track what APIs access which data, therefore giving you full visibility into the data pathways your organization relies on.

#2: Centralized Logs

Most organizations spend considerable time and energy securing their own networks. The foundation of security visibility is logs – small files that are generated whenever a network device or application does anything. They’re typically used in Security Incident and Event Management (SIEM) tools, to monitor the real-time actions of network-connected devices and users. 

Other internal security tools – like firewalls – also keep ongoing logs of the access and deny decisions they make. All logs represent valuable security data – and given the extended nature of today’s SaaS applications – it’s vital that this visibility extends into the databases you’re renting off each SaaS provider.  

Rather than managing logs in multiple dashboards, organizations should adopt centralized log management to:

  • Improve efficiency – Eliminates the need for security analysts to switch between multiple platforms.
  • Enhance threat detection – Provides a unified view of security events across both internal and SaaS environments.
  • Reduce manual oversight – Minimizes reliance on continuous manual log reviews, which are prone to human error.

#3: Behavioral Anomaly Detection

SaaS applications rely on tight integration with an organization’s wider data ecosystem.

While this could be seen as risky, it also represents a great use case for machine-learning-based protection. Because SaaS applications generate logs upon every single API call and transfer process, machine learning is uniquely well-positioned to ingest all of this access and handling metadata, and transform it into usable analytics. 

All parameters can now be tracked:

  • What databases the app accesses
  • Which users’ requests it serves
  • How much data it transfers at once

Over time, this application behavior is tracked and a baseline of normal behavior is created (sometimes this is expedited by the ingestion of historical logs, allowing for a new security solution to begin identifying behavioral abnormalities immediately). 

It’s not just individual applications’ behaviors that can be monitored for abnormalities – user accounts can also benefit from it. If an account suddenly exhibits unusual behavior, such as logging in from an unfamiliar location or performing high-risk actions, behavioral analysis can trigger alerts or enforce additional security.

#4: Automated Patch Management

App and SaaS users’ behaviors aren’t the only things that greatly benefit from automation. 

The security of SaaS tools’ code is the core product that a SaaS customer is paying for; this code is managed by the provider, whose DevOps teams work on maintaining it and removing bugs and flaws. These fixes are implemented via patches, which almost always need to be installed as quickly as possible. 

Failure to apply patches promptly can leave systems exposed to known exploits. because of the quantity of SaaS applications that most organizations use, installing new patches can quickly become delayed. 

Proper patch management should use automation that checks for available updates, and prioritizes them.

Keep SaaS Innovation Secure with Check Point SASE

Check Point’s SASE focuses on securing the entire data pipeline regardless of where that data is generated and stored. Harmony SaaS takes an ecosystem-wide approach to SaaS risk, mapping the full extent of your applications and APIs’ interactions from a single central console.

Our product dramatically increases your security teams’ performance thanks to its visibility into all connected cloud services, allowing IT teams to universally enforce policies that prevent data leakage – even for GenAI. Once application activity is discovered and mapped, IT and security teams are able to remediate SaaS security misconfigurations with a single click. 

Install in just a few clicks, gain rapid insight, and remediate gaps right from the console. Explore Check Point’s SASE with a demo today and start securing your SaaS ecosystem. 

FAQs

How do we assess the risk level of a specific SaaS integration before adoption?
Start with a security questionnaire and vendor risk assessment, reviewing items like ISO 27001 certification, SOC 2 reports, breach history, and API documentation. Tools that track OAuth scopes, API behaviors, and data access patterns can also give early insight into exposure risk.
What’s the difference between Shadow SaaS and Shadow IT—and why does it matter?
Shadow SaaS refers specifically to unauthorized third-party applications integrated with your core systems (e.g., a team using unapproved project management tools). Shadow IT is broader and includes any unsanctioned tech. Shadow SaaS creates silent data bridges to external parties, increasing risk without obvious signals.
Can third-party AI plugins leak sensitive data even if the core SaaS tool is secure?
Yes. Many GenAI plugins or extensions access external LLMs that don’t guarantee data isolation. Even when the primary SaaS platform is secure, plugins can create side channels for data exfiltration, especially if API scopes are overly permissive or poorly monitored.
Are SaaS security risks higher for startups or small businesses than for enterprises?
They can be. Startups often lack centralized visibility, rely on numerous SaaS tools to scale quickly, and may not enforce strict access policies. While enterprises face broader complexity, SMBs are often more vulnerable to targeted attacks through overlooked integrations.
How often should organizations review or re-certify their SaaS integrations?
At a minimum, conduct quarterly reviews of high-risk integrations and annual audits for all vendors. Any time a SaaS provider announces a major update, data breach, or policy change, reassessment should happen immediately to update controls or revoke access.

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