API Security: Understanding Types, Challenges, and Best Practices
Explore the types, challenges, and best practices to safeguard your valuable data. Discover key insights and expert recommendations to protect your APIs from cyber threats. Don’t miss out on enhancing your API security knowledge!
Table of Contents
The digital world has brought advancements in all sorts of life. The applications communicate with each other over the internet to deliver effective service. API is an application language that interacts with the application server to extract the client’s intended information and produce it readable.
It is estimated that the global API market will reach about 13.7 billion US dollars by 2027. This user-friendly software makes the business organization widely adopt it to enhance their growth. API handles the business information, customer details, product details, and more.
The increasing adoption of the API functions as a new gateway to cyber-attacks. Hence, API security plays a critical role in the organization. This article discusses API security, its necessity, challenges, and benefits in detail.
What is an API?
Application Programming Interface, commonly referred to as API, is an intermediate software. It provides secure communication between two devices, networks, or applications over the internet.
For example, the person wants to search a restaurant near him on a mobile phone. He types it on the search engine, which provides the list of the restaurants present in the locality. API acts as an intermediary between the person and the server to provide the required data from the database.
Application Programming Interface is implemented to ease the request of service or exchange of intended information process. The codes in the API are securely written to provide its request with the desired results. The customers, employees, and third-party organizations related to the business can read the intended data and benefit from it.
One of the key benefits of APIs is the ability to leverage code reusability. By encapsulating specific functionality or services into API endpoints, developers can create reusable components that can be easily accessed and integrated into multiple applications.
Types of API
Public API is also known as open API, a software language used by application users. It’s open and available for use by any outside developer or business. It is used to share standard information among third-party users. Open API usually has low authentication that helps users access the resources quickly without any restrictions.
For example, Google maps uses an open API where the route’s traffic details can be viewed by any users from any location.
Partner API is used to limit resource access to authorized business clients. It monitors the resources and helps to enhance security. It is effectively used to conduct business among the two or more clients to share the intended business information outside the organization securely.
The Partner API also provides customization options. This allows organizations to define the level of access and specific functionalities that their partners can utilize, ensuring flexibility while maintaining data privacy.
Internal API is used to access the resources internal to the organization. It involves information about various levels of the organization. As a result, the personnel internal to the organization can access these resources quickly. In addition, it helps restrict the threats and vulnerabilities entering the resources from open source.
Composite API combines two or more APIs used to manage the resources effectively. The hybrid API is used to perform multiple tasks related to business activities. It helps the developers to provide service to more requests. As a result, composite API improves the performance and efficiency of the business process.
How do APIs work?
API is designed with codes to receive the request and respond with the result between the applications. It is a software language that provides effective communication between applications.
The working of API follows the following steps.
- The user initiates a request through the web application over the internet.
- The API receives the request sent by the user application.
- The API collects the information from the server connected to it.
- The collected data is delivered to the requested application.
For example, Person A wanted to search for a hospital near him. He searches for the hospital near him in a mobile application or website search engine. API received the request demanding the hospital near the user location. It collects all names of the hospital from the database. After the information is collected from the database, the API displays the results through the search engine. These processes occur in a fraction of time to deliver effective service to users.
Thus, API serves as a medium of communication between two applications.
API securely connects two or more applications to deliver the user’s request. Hence, it is a vital part of the organization in providing essential service to its customers. The fourth state of the API Integration Report of 2020 states that 83% of business organizations adopt API integration to their business functions and experience tremendous growth.
Types of API Architecture
API architecture refers to the structure and design principles used in developing application programming interfaces. Common types of API architecture include REST, SOAP, and RPC.
- REST is Representational State Transfer Architecture, a commonly adapted API approach for a web application.
- It provides a flexible client-server system to receive and respond to users’ requests.
- The communication protocol used is HTTP to request and respond to the user.
- It does not store any requests and responses. Instead, it responds to each incoming request.
- SOAP is a Simple Object Access Protocol that is highly structured with defined standards.
- It is the most secure API and is used for critical applications.
- It is accessible to any communication protocol and uses XML to encode information.
- RPC is a Remote Procedural Call that is used in basic internal processes.
- It uses both JSON and XML to respond to requests from the client.
- It receives multiple parameters to deliver a response and is used to execute the actions in the servers.
- It is a secure and straightforward API to work on remote networks.
API Security Challenges
The weaknesses in API attract attackers to capture the company’s critical resources. The security challenges occurred from improper security features, authentication, and access control. Knowing the security challenges helps the developer quickly identify and secure the API from internal and external threats. Some of the Security challenges commonly found in the API are as follows.
Broken Object Level Authorization
Broken object-level authorization is a common API security challenge that occurs when the mechanism controlling access to resources or objects within an API is flawed or improperly implemented. This vulnerability allows unauthorized users to gain access to sensitive information or manipulate resources they shouldn’t have access to.
Prevention – To mitigate this challenge, developers must define and enforce proper access controls based on user privileges, roles, and the sensitivity of the resources.
Broken User Authentication
Broken user authentication is an API security challenge that arises when authentication mechanisms are weak or improperly implemented. This vulnerability enables malicious actors to gain unauthorized access to user accounts or sensitive information.
Prevention – To address this challenge, developers should enforce strong password policies, implement secure password reset functionality, and employ multi-factor authentication where possible.
Redundant Exposure of Data
Redundant exposure of data is a significant API security challenge that occurs when APIs provide access to more data than necessary, potentially exposing sensitive or confidential information to unauthorized users.
Prevention – To mitigate this challenge, developers should adopt the principle of least privilege, ensuring that APIs expose only the minimum required information. Data anonymization and pseudonymization techniques can also enhance data privacy and minimize the risk of exposing personally identifiable information.
Inadequate Resources and Request Management
The attacker sends the request to the API than the specified limit. As a result, it leads to denial of service or interruption of its function.
Prevention – The developer can avoid it by limiting the number of resource allocations and the number of requests processed by the API at the given time. Then, it will notify the application to process requests within the specified limit.
Disrupted Function Level Authorization
Authorization acts as a gateway to the critical resources of the organization. The issues in the authorization mechanism enable access to the sensitive resources of the organization. The attacker sending requests to such resources will gain access and steal the data.
Prevention – It is avoided by applying multi-factor authentication to allow authorized users access to sensitive resources.
Mass Assignment speeds the request process by delivering the input request by automatically assigning the object properties. However, the attacker can alter the object properties to access the organization’s critical resources. It is rectified by manually setting the object identifier and using tools to monitor the abnormal functions of the API.
Prevention – To prevent mass assignment vulnerabilities, validate and sanitize user input thoroughly, implement strict input filtering, and utilize a whitelist approach for accepting only trusted and expected properties during object assignment.
Security Misconfigurations in API
API misconfiguration refers to weaknesses found in the server favourable for cyber-attackers. It acts as a gateway for cyber threats to enter the organization and disrupt the entire functionalities.
It occurs at any level of the organization, from the system level to the application level. The flaws in the systems, access, and data lead to the compromise of API. It leads to severe data breaches and the stealing of sensitive organizational resources.
Some common misconfiguration that occurs in the Application Programming Interface that question the security of the organization include,
Insecure Data Storage and Data Transmission
The organization’s sensitive data, including confidential files, customer details, account details, are not properly encrypted and stored in the databases. As a result, it leads to data breaches that cause severe effects on the organization. In addition, the leakage of critical data brings down its reputation to affect its growth and customer satisfaction.
Passwords play a critical role in the security process. It acts as a key to access all sorts of accounts. The passwords are appropriately secured to avoid unauthorized access to essential resources. However, using the same password across all the web applications opens a threat to the organization. Therefore, a proper encryption technique must be followed while sending from one user to another. In addition, the passwords should be encrypted before storing them in any file location.
The security misconfiguration causes severe damage to the organization. The early detection of the misconfiguration helps the organization strengthen its ability to protect from cyber threats. The automated process should be employed to detect the security misconfigurations in API and resolve it.
Cyberattacks on API
Hackers often target APIs due to their increased usage and interconnectedness in modern applications. Here are some common cyberattacks attempted on APIs:
The standard attacks on the Application Programming Interface include Man-In-the-Middle Attack, Cross-Site Request Forgery Attack, Cross-Site Scripting Attack, SQL Injection, Distributed Denial of Services, and more.
A man-In-the-Middle attack is a critical cyber threat with everyday organizational work. The attacker places himself between the two users to collect sensitive data or unauthorized access to the resources. Unfortunately, the management remains unaware of such attacks until the consequences are exhibited.
The attacker’s motive is to steal sensitive information, transfer funds, and monitor critical processes.
How to prevent Man-In-the-Middle Attack?
To prevent Man-In-the-Middle attacks, organizations should implement strong encryption protocols such as HTTPS to secure communication channels between users.
An essential part of implementing HTTPS is the use of a Secure Sockets Layer (SSL) certificate. SSL certificates work like a digital passport, verifying the authenticity and identity of a website and reassuring users that they are communicating with the intended organization and not an imposter. Therefore, adding an SSL certificate to enable HTTPS is a critical step for organizations to mitigate man-in-the-middle attacks.
Cross-Site Request Forgery Attack (CSRF Attack)
Cross-site Request Forgery Attack is when the hacker captures the victim’s account to conduct malicious activities from the authorized source. It usually takes place to steal the account details, transfer funds, and steal sensitive information. The victim remains unaware of the hidden activities happening through the account.
How to prevent Cross-Site Request Forgery Attack?
Cross-site Request Forgery Attack is prevented by validating the user request to check its origin. The authorized connection is allowed to ensure the secure transfer of resources.
Cross-Site Scripting Attack (XSS Attack)
Cross-Site Scripting Attack is an injection attack where an authorized source sends the script-injected link to the victim. The victim assessing the document from the attacker gets infected by the malicious content present in the link. As a result, the attacker can easily access the personal and official range of the victim. It is used to gather login credentials, passwords, and account details to steal sensitive resources.
How to prevent Cross-Site Scripting Attacks?
Cross-Site Scripting Attacks are avoided by neglecting the content from unknown users. Additionally, the email validation ensures their resistance to malicious content.
Distributed Denial of Services
Distributed Denial of Service is a type of Denial of Service where the attacker floods the server to disrupt the functions. It results in minor interruption of the service to the long-time system downtime. The professionals are unable to identify such threats as it looks like legitimate traffic. Distributed Denial of Service in API interrupts the data transmission between the two applications. Thus, it causes system failure, revenue loss, and customer satisfaction.
How to Prevent Distributed Denial of Services attack?
To prevent Distributed Denial of Service (DDoS) attacks, organizations can implement several measures. These include using traffic filtering systems to detect and mitigate abnormal traffic patterns, employing load balancers to distribute incoming traffic evenly across multiple servers, and implementing rate-limiting or throttling mechanisms to limit the number of requests from a single source.
SQL Injection is a cyber threat that allows the attacker to insert the SQL queries on the database to view and read the content. As a result, the database is compromised to obtain critical organizational information. The recent SQL Injection attack resulted in data breaches leading to loss of the company’s reputation and financial damage. SQL injection, if left unnoticed, leads to long-term compromise of data resources.
The best security practices ensure the opportunity to identify and neglect the possible cyber threats affecting the Application Programming Interfaces.
How to prevent SQL Injection Attacks?
To prevent SQL Injection attacks, developers should implement secure coding practices such as input validation and parameterized queries. They should avoid concatenating user-supplied input directly into SQL statements and instead use prepared statements or parameterized queries with placeholder values.
Sometimes, hackers may exploit the functionality and permissions granted by an API to abuse its resources. For example, they may use an API to perform repetitive actions, such as brute-forcing passwords or scraping data in large volumes, causing service disruptions, performance issues, or unauthorized access.
How to prevent API abuse attacks?
Implement a robust authentication mechanism to ensure that only authorized users or applications can access the API. Additionally, enforce strict authorization policies to limit access to specific resources and functionalities based on user roles and permissions.
What is API Security and why is it important?
API security refers to the tools and processes employed to defend against threats and vulnerabilities. A secure environment provides more efficiency and increases the productivity of the organization. As API shares the organizational data with third-party users or applications, it is mandatory to security check the procedure for weaknesses.
Importance of API Security
Secure Communication Between the User and the Application
Application Programming Interface is widely adopted by organizations to effectively communicate with their customers and partners. Effective communication and better service will enhance customer satisfaction and promote business among the people. The motive of the API is to deliver effective service to its customers. It is achieved through lines of codes shared through a tool called application. Secure communication between the organization and its users is achieved through adopting API security measures.
API is a Primary Target for Cyber-threats
API allows the users to access the intended information from the company’s resources. It also acts as a suitable landscape to execute cyber-attacks like SQL injection, Denial of Service, Social Engineering attacks. The attackers find this medium a weak source to enter the organizational network and capture the data. The successful attack severely affects the organization’s functions due to leakage of sensitive information and seizure of the systems. The installation of security tools will help secure API functions securely from cyber-attacks.
It helps in the growth of the organization.
API gateway acts as the path to access the organizational information. It is used by individuals, employees, partners, and third parties associated with the organization. The compromise of API at any level leads to severe loss to organizational reputation and growth. In addition, the organization suffers from loss of revenue, customers, and resources if the API is compromised or attacked. Hence, API security is essential in the practical and productive functioning of the organization.
It Maintains the Business Standards
Each organization follows the business standards to function in its competitive world effectively. The API security implementation maintains the standards in the business services to achieve customer satisfaction and attain organizational goals.
Promote Organizational Security
Application Programming Interface interacts with the third-party applications to deliver the user’s intended information. The API security will identify the threats and vulnerabilities present in the third-party applications and promote organizational safety. The threats and vulnerabilities present in the other applications may disrupt the entire function. It may lead to system failure, malware attacks, and data breaches.
API Security Testing
API security testing is the process of determining the vulnerabilities and threats present across the API. It can be an automated process or done manually to ensure performance against cyber threats. The results obtained through the security testing process helps to create remedial solutions against cyber-threats. The system errors and flaws are also found in the API security Testing.
Principles of API Security Testing
API security testing follows five fundamental principles that help the API defend against incoming attacks. The security test that satisfies the principles works effectively in the threat environment.
- Inputs fed into the API are checked for the specified format. The non-specified format of the information is rejected to avoid threat access.
- The input size is verified whether it stays within the specified size designed for the intended API.
- API is examined whether it produces the desired result for the given input.
- API input values stay within the expected domain to process the request. Therefore, the importance of input outside the field is rejected for effective API functioning.
- API processes the request and produces the clients with the desired result accessible for the requested client. The API must reject the unauthorized access request to maintain the security of the resources.
Types of API Security Testing
API security can take different testing depending upon the function it performs. It is taken to check the attack vectors present in the API structure, scan code for the flaws and errors, and compare the API with the known vulnerabilities and threats.
The types of API Security include
Dynamic API Security Test
A dynamic API security test is performed to determine the known vulnerabilities present in the API. The testing team introduces the threats and error code into the API to determine the performance of the API with the situation.
Static API Security Test
Static API security test compares the source code of API with the testing tool. The testing tools aim to obtain the extracted match for the code, and other irrelevant codes are considered threats.
Software Composition Analysis
Software Composition Analysis evaluates the API against the known vulnerable database to identify the known threats. The identified threats are updated to the database to identify the threats entering the API
The most effective test results are obtained when all three tests are performed to ensure the most secure API.
Top Open-Source API testing Tools
These open-source API testing tools provide powerful features and flexibility, enabling testers and developers to effectively validate and ensure the quality of their APIs without the need for expensive proprietary solutions.
Postman is a widely used and highly popular open-source API testing tool. It provides a user-friendly interface for designing, testing, and documenting APIs. With Postman, you can easily send requests, validate responses, and automate API testing. It supports various protocols and offers features like test scripting, test data management, and collaboration capabilities.
REST-assured is an open-source Java-based library for testing RESTful APIs. It provides a domain-specific language (DSL) for creating expressive and readable API tests. REST-assured allows you to write tests concisely and intuitively, making it suitable for both beginners and experienced testers. It supports various authentication methods, JSON/XML parsing, and assertion libraries, making it a powerful tool for API testing.
SoapUI is a widely used open-source tool for testing SOAP and RESTful APIs. It offers a comprehensive set of features for API testing, including functional testing, load testing, and security testing. SoapUI provides an easy-to-use graphical interface for designing and executing tests, and it supports various protocols and standards. It also allows for data-driven testing, assertions, and test reporting, making it a versatile tool for API testing.
Common API Security Tests
The security auditing process ensures the secure functioning of the API in the vulnerable and threat environment. The test takes place in the security auditing process included.
- Security testing verifies that the intended API meets the security criteria to protect itself from misconfiguration and human errors.
- The security issues, including authorization issues, are taken up during the testing. API verifies the client’s identity before providing the result to avoid unauthorized access.
- The encryption algorithm used for encrypting the data during transmission is examined, and performance is evaluated with the latest threat trends.
- The access mechanism checks whether the API provides the client with the permissible content. In addition, the tool employed for the process is accessed to determine its functionality.
- The tools and techniques employed in the API are verified for accuracy and efficiency. In addition, it helps developers update and replaces the latest tools and methodologies.
Penetration testing is basic testing done to determine the security of the API gateway. It is better to prevent the threats at the gateway than to wait till it reaches the internal system.
- The records of the attacks and threats are maintained in the directory at each instance.
- The duplicate attack is initiated by the API to determine its performance with the defined vulnerability.
- The developer determines the compromise sections of the API. The secure layer of the API is also identified.
- The obtained result is recorded for future reference.
- The security measures are undertaken to rectify the compromise or affected parts of the API.
- It determines the areas to be secured from threats entering the organization.
Fuzz testing is the last test in the auditing process. It interrupts the entire API from processing the request and causes a system failure. After that, the API is affected by unauthorized access or threats and unlimited request processing.
- The API is checked by sending the request over its limit, and its performance is verified.
- The API either rejects the request exceeding its limit or gets interrupted by processing the request. Effective measures are taken to deal with denial-of-service attacks.
Parameter for API Security Testing
Test for API Input Fuzzing
Fuzzing is the process of inputting some random input data to receive the desired output or output containing vulnerabilities, threats, errors, and bugs. The API to be assessed is fed into the test tool, and it scans the entire API. Once the scanning process is completed, the errors, flaws, and vulnerabilities detected are displayed in the output.
The automated tool used for the API input fuzzing is Fuzzapi. It is an open-source fuzzing tool used to detect the threats available in the API. For example, it identifies cyber threats like cross-site scripting cross-site request forgery attacks.
Test for API Injection Attacks
API injection Attacks test is employed to determine the attacks like SQL injection and command injection. SQL injection takes place to access the critical organizational databases. Command Injection changes the purpose of the internal code functions.
Sqlmap is a tool to automatically evaluate the process of SQL injection in the API. First, the SQL command is input to the API. Then, depending upon the error message, the method will determine if the API is vulnerable to SQL injection or not.
If the input SQL command outputs 200, it is called error-based SQL injection. If the input SQL command outputs 500 internal errors, the system is non- error vulnerable SQL injection.
Commix is the automated process to determine the command injection. The malicious code is embedded along with the API code to disrupt the function of the specific API endpoint. Hence, it is necessary to determine such a threat early to rectify the API endpoints.
Test for Parameter Tampering
Parameter tampering is the process of unauthorized change in the functional parameter of the API request and response. The attacker employs this kind of technique typically in the online shopping process. The attacker can change the product’s value using a hacking mechanism and purchase products free of cost.
Test for Unhandled HTTP Methods
API communications over web applications are done using the different HTTPS Methods. HTTPS methods are employed to store, retrieve, remove, and output the requested data.
- A request is sent to the API endpoints using the API URL that undergo testing.
- If the result obtained is 405 methods not allowed 501, the system is working in good condition.
- If the result is 200 ok without authentication, it is a sign of threat or vulnerability.
API Security Best Practices
Educate the Employees
Employees are the pillars of the organization for smooth functioning at all levels. Everyone undergoes training sessions on the recent technologies and ways to protect API from attackers. It helps them to identify threats effectively to defeat the attacks being initiated. Common API threats like cross-site request forgery attacks and forms of social engineering can be cracked by the employees.
Continuous Monitoring of the API
An automated process is employed to monitor the API functionalities continuously. API is viewed for regular functioning, errors, malware, attack vectors, traffic. The captured data regarding the abnormalities are recorded as documents used during emergencies.
API undergoes regular testing to determine whether it functions upon standards. It helps to identify the flaws, errors, performance of the API in the network. The recorded information helps to take remedial actions to rectify the faults and boots the effective functioning.
Maintain the Entire Work Function
The security and performance of any system are improved by constantly maintaining the system. The proper maintenance will increase productivity and provide efficient service to the customers. The API is updated with the latest version of the market. In addition, the hardware and software associated with the API are verified to determine its efficiency.
The use of basic authentication cannot meet the latest requirements of API. A robust authentication mechanism ensures better safety and reliability of the authentication and authorization.
Securing the API Endpoints
The API endpoint is a URL where the request is made, and the responses are received. API endpoints are integrated with the authentication mechanism to prevent unauthorized parties from accessing critical resources. The users with the secret key are allowed to access the API to avoid security problems. Each API endpoint is secured to protect itself from threats.
Knowing the Integration Partner
API integrations are sharing organizational data between various applications and systems. Though the corporate API is secured with the latest tools and techniques, the insecure third-party API leaves the API compromise. As a result, it leads to data breaches and exposure of sensitive data. Therefore, the automated process should be employed to continuously monitor the third-party applications for all sorts of threats and vulnerabilities.
Employing the Right Security Strategy
The API gateways security is essential in secure API functioning. The standalone security systems and firewall provides security to the API. Investing in the external security tools and leaving the API gateway unsecure to create an entry point for vulnerabilities and threats.
API Security Products
These products are designed to enhance the security of APIs and protect them from various threats and vulnerabilities. API Gateway and Web Application Firewalls act as protective shields and help manage and secure the flow of API requests and responses. Standalone security products provide additional layers of protection and monitoring against incoming threats, while security in code ensures the integrity and security of the API code itself.
API gateway acts as an entry point for client requests and the exit point for the application responses. It manages the client request and response and the back-end services of the API.
API gateway acts as a protective shield to the organizational resources. First, it helps to identify the API endpoints of the organization. It secures the API endpoints from the attacks that disrupt the entire purpose of the API. The standard attacks detected and defeated by the API gateway include SQL Injection, Denial of Service, Cross-site scripting. It also helps manage the data flow across the network to avoid unnecessary traffic and system downtime. Finally, the API gateway monitors the system’s performance to deliver efficient service to the client’s request.
Web Application Firewalls
Web Application Firewall acts as a protective shield between the client and the API. It filters out the valid request to the API to deliver a response to legitimate clients. The vulnerable sites’ requests are quickly identified, and their request is rejected. A simple help to determine the common threats and vulnerabilities entering the Application Programming interface.
The recent inclusion of Artificial intelligence in the Web Application Firewall helps to remove advanced cyber threats and vulnerabilities. The bot attack, the signals of attacks, invalid IP identification provides added advantages to the WAF. It is also employed to detect common API attacks like SQL Injection, Cross-site scripting attacks, HTTP protocol violations, and malware.
Standalone Security Products
Standalone security products play a significant role in API security. The products add extra protection to the inbuilt schemes to protect the API from attackers. The standalone security products provide real-time monitoring, identification, protection against incoming threats and vulnerabilities. In addition, the security products offer the remedial measure to retain from the attacks.
There are a variety of standalone security products available in the market. The organization must choose the desired outcome based upon the API function and its requirements. Some commonly available products include Astra, crAPI, Curity Identity Server, Hawk, OAuth, and more.
It identifies attack vectors malware to strengthen the system from attacks. It is also used to validate the users and verify the authentication.
Security in Code
Application Programming Interface is lines of code written to perform the request and response between the two applications. The API code security prevents the hacker from modifying the code to disrupt the function. In addition, the secure code will provide better performance to increase the efficiency of the working process.
Benefits of API Security Testing
- It identifies and prevents threats and vulnerabilities from entering the API.
- The result obtained from the API security Testing helps the organization create strategies to empower the API and the organization.
- It filters out threats and detects internal source code bugs and logic errors.
- It verifies whether the API is working depending upon the standards and specifications.
- It scans to determine the API endpoints work upon the specified requirement. The deviation in the API endpoints is identified, and remedial measures are established to resolve it.
The application programming interface is a bridge between the user and the organizational database. So, it is necessary to secure it from all types of threats and vulnerabilities affecting its functions. The API has the source code to build up or break down any business. Hence, choosing the proper security mechanism and updating its latest features will resist cyber threats.
API security testing procedures are employed to maintain the secure functioning of the API. Though the API provides secure communication and user-friendly software, it is also a primary target for hackers. The right strategy creates a safe environment to cherish all the benefits of the API. Thus, it uplifts the growth and reputation of the organization.