API attacks are constantly on the rise, with a recent alarming study showing that 59% of organizations give out ‘write’ access to at least half of their APIs, which leads to unauthorized access by hackers.
API interfaces help with smooth communication but are usually not focused on digital protection. The risk of hackers accessing and altering data via APIs makes them prime targets for data theft, account takeover, and various harmful attacks.
What are APIs?
APIs (Application Programming Interfaces) facilitate communication and data exchange between software applications, allowing easy integration across various platforms, services, and devices. They drive everything from mobile applications to complex enterprise systems and dictate how distinct software components communicate, detailing the requests, responses, and data formats involved.
Common API Attack Vectors
1. Broken Object Level Authorization (BOLA)
BOLA occurs when authorization fails to secure particular data objects in an API. A hacker can gain unauthorized access to users’ data by manipulating the object ID sent in API requests.
An example is how users retrieve their shopping order information by supplying an order ID to an e-commerce API. The attacker can change the order ID parameter and gain access to the details of a completely different user’s order. This same vulnerability/attack vector can be exploited in more sensitive sectors like banking or healthcare, leading to the leak of personal data.
2. Broken User Authentication
This occurs within the authentication system when users maintain inadequate passwords, implement flawed token management systems, and elevate the need for multi-factor authentication.
Attackers use potential system vulnerabilities to obtain unauthorized access to end users’ accounts. The API implements weak verification codes as part of its password reset functionality.
3. Excessive Data Exposure
API systems that deliver excessive data expose users to the risk of revealing private information, which hackers, in turn, leak or use to their advantage. This is done to disclose financial details, sell health metrics or contact details to private institutions, etc.
This attack vector takes place when a system provides details of the complete user profile containing sensitive information that exceeds the necessary data requests and is beyond the hacker’s authorized access.
4. Lack of Resources & Rate Limiting
Implementing rate limiting and resource management in APIs protects them from denial-of-service (DoS) attacks and API abuse. When attackers send excessive requests that exceed the API’s processing capability, the API becomes unreachable to legitimate customers, resulting in a server outage.
A security flaw occurs when an API enables unlimited function requests through which attackers gain access and this can be rectified by employing API penetration testing tools.
5. Security Misconfiguration
Security settings, API server configuration, and infrastructure errors make up this issue. API systems are at risk when maintainers leave default access credentials, activate debug endpoints, or enable insecure HTTP features.
The cloud storage API does not have the required proper configuration, which results in unauthorized public access to sensitive files.
6. Injection Attacks
The attack technique of injecting corrupted code through API requests is similar to SQL injection attacks. Attackers use the open or available vulnerabilities to control information, execute commands, and perform unauthorized system access. An API that accepts user input to build database queries but lacks necessary sanitization measures functions in this way.
7. API Abuse
Hacking behaviour by abusing APIs includes data scraping, fake account creation, and API exploitation. The API allows an attacker to build numerous fake accounts, which they then use for spam, data fraud, and theft.
Proactive Strategies for Securing Your APIs
1. Authentication and Authorization
Thorough authentication and authorization controls are essential for safeguarding API platforms. By implementing coarse access control methods like Role-based access control (RBAC) or Attribute-based access control (ABAC), you can protect vital resources and minimize the impact of vulnerabilities during security incidents.
As such, you should continuously adapt the principle of least privilege, and by doing so, organizations enhance their security posture, beginning with a default denial of access and granting permissions only for essential needs.
2. Strict Input Validation and Sanitization
The prevention of injection attacks depends heavily on validating and sanitizing all user entries against the pre-established rules and conditions. The correct formatting procedures prevent data violations and stop manipulations and attempted code attacks to protect APIs.
This will help you establish systematic security and prevent any manual errors that can arise during the security process.
3. Rate Limiting and Throttling
API security requires rate limiting and throttling implementations, which help prevent denial-of-service attacks and API abuse. Allowing only a limited number of requests during specified periods keeps APIs functional and ensures fair usage.
API usage patterns should be analyzed as the basis for defining the rate limit along with endpoint-specific rates and error messages that guide users about exceeding limits.
4. API Gateways and Web Application Firewalls (WAFs)
Applications Program Interface gateways and Web Application Firewalls serve essential functions in maintaining API security. API gateways act as a unified access point that essentially executes authentication measures and authorization procedures, as well as traffic management supervision. On the other hand, WAFs defend systems from web-based assaults such as SQL injection and XSS.
These security tools are able to deliver the needed protection by examining API communication to handle premeditated payloads and prevent well-known attack activity. APIs are then capable of defending against Broken object-level authorization attacks (BOLA attacks) alongside other threats by implementing authentication policies and rate-limitation security measures.
5. Regular Security Testing and Audits
API security audits assess the overall security posture of APIs and verify whether standards such as GDPR and HIPAA have been adhered to. Security audits with compliance checks help maintain strong security positions while minimizing potential financial penalties for organizations.
6. API Security Best Practices
API versioning is one of the security practices that help developers introduce new features without disrupting linked components. It helps manage and track how APIs change and evolve.
Aside from this, encryption can enable you to safeguard data as it is being transferred between servers and also when it is stagnantly stored. By combining comprehensive logging with event monitoring, users can identify any and all unusual activities, and be able to pinpoint possible security incidents based on API activity data.
Final Thoughts
Implementing API security in a year like 2025 with the consistent growth we’ve been experiencing in the complexity of API attacks, such as AI-driven attacks, can be confusing and difficult. There has never been a more crucial time to stay up-to-date on your API Security.
Organizations should establish holistic authentication and authorization protocols for adequate API security, along with thorough input validation and effective rate-limiting strategies. Eventually, an organization’s overall API security can be improved via the synergy of API gateways with WAFs, continuous testing, and following security best practices, such as API versioning and data encryption.
A strong and unpenetrable API protection framework requires you to incorporate advanced security measures, enable proactive security monitoring, and embrace a defensive security mindset.
