Best API Security Practices for the Protection of Sensitive Data
Application Programming Interfaces (APIs) allow app developers to pull information from external sources. They simplify the coding process by giving developers access to a large amount of data they would otherwise be unable to access.
APIs benefit providers too. They create new revenue possibilities by making valuable data and services available, usually for a fee. Consumers are also winners. They benefit from innovative, feature-rich, interactive apps that provide many services all in one place.
But with all this personal information swirling around, how can companies stay data-compliant and protect data privacy? Read on to learn about the best API security practices.
Highlights
- APIs are essential for modern app development but they may also pose huge security risks if they are not properly protected.
- Data breaches can cause serious penalties under laws and regulations.
- Most API security risks boil down to improperly set up access controls, mismanaged protocols, and a lack of dedicated security measures.
- Proper API security can be ensured with the help of dedicated software.
Why Having a Data Security Strategy Matters
Faulty, hacked, or exposed APIs lie behind many major data breaches. These types of instances shine a light on sensitive personal data that is not for public consumption. The consequences for a company can be catastrophic.
Data laws and regulations mean there can be eye-watering fines for any breaches. However, not all data are the same, and the way you tackle API security will depend on the kind of data that gets transferred.
For example, when an API connects to a third-party application, an individual might want to limit some information about them. That might include tracking their location but not knowing about their favorite vacation destinations.
What Are the Most Common API Security Risks?
API security risks are vulnerabilities or weaknesses that can be exploited to compromise the integrity, availability, or confidentiality of an API and its data. Some of the most common API security risks include:
- Broken Object-Level Authorization (BOLA): Failure to implement proper checks to ensure that users can only access the objects to which they have permission.
- Broken User Authentication: Inadequate authentication mechanisms that allow attackers to assume legitimate users’ identities.
- Excessive Data Exposure: Over-fetching of data where the API exposes more data than is needed for a particular function, potentially leading to data leaks.
- Lack of Resources & Rate Limiting: Without proper rate limiting, APIs can be vulnerable to Denial-of-Service (DoS) or brute force attacks, where an attacker overwhelms the API with requests or attempts to guess credentials through repeated trials.
- Broken Function Level Authorization: Incorrectly implementing function-level permissions that allow users to perform actions they shouldn't be allowed to do.
- Mass Assignment: Allowing attackers to modify object properties they shouldn't have access to through APIs that bind client-provided data to data models.
- Security Misconfiguration: This can include unnecessary HTTP methods, verbose error messages containing sensitive information, or misconfigured HTTP headers among others.
- Injection: Injection flaws, such as SQL, NoSQL, Command Injection, etc., occur when untrusted data is sent to an interpreter as part of a command or query.
- Improper Assets Management: Improperly managed APIs can expose endpoints that are more sensitive and should not be publicly discoverable, and undocumented APIs can be exposed unintentionally.
- Insufficient Logging & Monitoring: Inadequate logging and monitoring make it difficult to detect or respond to breaches on time, potentially allowing attackers to exploit other vulnerabilities before they can be addressed.
- Use of Components with Known Vulnerabilities: Using libraries or software components that have known vulnerabilities can leave an API open to exploitation.
- Incorrect Content Handling: Misinterpreting the content by not validating the MIME type, for example, can lead to the execution of malicious code or scripts.
Addressing these risks typically involves implementing robust authentication and authorization checks, validating and sanitizing inputs, implementing access control at multiple levels, rate limiting, logging, monitoring, and regularly updating components and dependencies.
Some Common Best Practices for Securing APIs
Companies need to adhere to API security best practices. They should employ well-established security controls if they plan to share their APIs publicly. Here is the lowdown:
1. Choose the Right Web Service API Protocol
The two API architectures that are most commonly used today are SOAP (Simple Object Access Protocol) and REST (Representational State Transfer). Each has its own set of standards, practices, and operational methodologies.
Security-wise, SOAP has built-in support for WS-Security, which can offer comprehensive security features like message integrity, confidentiality, and multi-factor authentication.
For REST API, security is implemented at the transport level using HTTPS. There are no built-in security features, so any additional security measures need to be implemented by the developer. However, it allows for more flexibility.
2. Use an API Gateway
Using API gateways acts as a protective barrier for services, adding a layer of security by enforcing authentication and authorization measures, validating request payloads, and protecting against common threats such as SQL injection, cross-site scripting (XSS), and cross-site request forgery (CSRF).
3. Create an Inventory
It doesn’t matter if an organization has a few or hundreds of publicly available APIs. Any one of them could help a malicious factor access sensitive data. That’s why a company should conduct perimeter scans to find and keep a list of its APIs. Then, they should work with their DevOps teams to manage them.
4. Implement Authentication and Authorization Solutions
Weak or non-existent authentication and authorization are huge issues with lots of publicly available APIs.
Broken authentication happens when APIs do not enforce it. This often happens with private APIs that are for internal use only or when it’s possible to break an authentication factor easily.
Because APIs can offer an entry point into an organization’s databases, organizations have to operate strict controls to access them. When possible, companies should use solutions focused on proven, appropriate tools. Safe and secure solutions include JSON web tokens, OpenID Connect, or OAuth 2.0.
5. Use the Principle of Least Privilege
Companies should only grant users the minimum access necessary for them to carry out their roles, narrowing access to sensitive data. This always applies to APIs.
6. Encrypt Traffic
Some companies may choose not to encrypt API data they consider to be non-sensitive. This could cover things like weather service information. Organizations whose APIs swap sensitive data such as banking or health information should always use Transport Layer Security (TLS) encryption for API requests as well as API responses.
7. Get Rid of Information That’s Not for Sharing
Companies should apply the principle of data minimization and remove any data that they do not intend to share. Since APIs are generally used by developers, they can contain passwords, keys, or other sensitive information.
8. Don’t Expose More Data Than Is Essential
Some APIs expose far too much data. This could relate to the quantity of superfluous information that gets returned through the API. It might also include information that reveals too much about API endpoints.
This usually happens when an API leaves the task of filtering data to the user interface instead of the endpoint. Companies need to make sure that APIs only return as much information as is necessary to fulfill their function.
9. Data Access Enforcement, Thresholds, and Firewall
As well as this, organizations should enforce data access controls at the API level. They should also monitor data and obscure it if the response contains confidential data.
Organizations should never pass input from an API through to the endpoint without validating it beforehand. They should also set a threshold over which further requests will face rejection. For example, they might allow a maximum of 12,000 requests per day for every account. This can help to prevent “denial of service” (DoS) attacks.
Companies can also use what’s known as throttling. This means slowing a user’s connection down while still allowing them to use your API.
Organizations should always use a firewall that’s able to understand API payload.
10. Log API Activity
When a company suffers a successful hack into its system, it needs to be able to trace the source of the incident. This helps with reporting and putting any problems right.
Logging all API activity is important. If an attacker breaches your protective shield, you can then make a judgment about what and how it happened. This can all help to improve security and reduce the risk of similar incidents in the future.
11. Carry Out Security Tests
It’s vital not to wait until a real attack to see how a company’s safeguards hold up. Organizations need plenty of time for security testing as a way of rooting out potential vulnerabilities. They should test routinely, especially after any API updates.
12. Use a Scanning Tool
A scanning tool such as iDox.ai can help limit any accidental exposure of information that’s not meant for the public domain. Clever technology will sift through files and documents and automatically pick out sensitive information.
This has huge advantages because manually performing this kind of process is time-consuming and ultimately expensive. Using a tool like iDox.ai frees up valuable time and effort better spent on growing a business.
13. Stash Your API Keys
An API key is a sensitive token that grants access to external services and resources. If they are exposed in the source code, particularly in public repositories, unauthorized users could gain access to your APIs and misuse them. This could lead to data breaches, service disruptions, or financial loss if, for example, the keys are used to access paid services.
14. Manage Claims via a Central OAuth Server
A central OAuth server allows for a single point of administration for identity and access management. It's easier to safeguard data privacy and enforce security policies, like multi-factor authentication, password policies, and access controls, when all claims are issued and managed centrally.
15. Regularly Validate the Data
Regular validation helps prevent malicious data from entering the system, which could otherwise lead to security vulnerabilities such as SQL injection, cross-site scripting (XSS), command injection, and other types of attacks. It's an essential part of application layer security that helps to ensure that only expected and correctly formatted data is processed.
Try iDox.ai Today
iDox.ai can save you time and money by reducing the risk of data breaches and ensuring a more robust API security environment.
Contact us today to try out iDox.ai and learn how it can help your organization with data compliance issues.
Frequently Asked Questions
What Is the NIST Standard for API Security?
API security falls under the NIST-800-53 compliance standards.
What Is an Example of An API Security Breach?
One high-profile example of an API security breach is the Facebook data scandal involving Cambridge Analytica, which came to light in early 2018.