What is API Security? Key Threats, Tools & Best Practices
Tzvika Shneider
August 18, 2025
9
min to read
Having spent years working with API-first teams in high-pressure environments, one pattern repeats itself across industries. APIs do not usually fail in the obvious places. Incidents often stem from overlooked test routes, undocumented endpoints, or delayed authentication controls. The breaches at T-Mobile and Peloton did not result from advanced exploits but from basic gaps in visibility and enforcement. This article builds on lessons learned in the field and explores the risks that continue to surface, the tools that address them, and the practices that help teams stay ahead.
Key Takeaways
API security protects against unauthorized access, data leaks, and service disruption by securing how APIs are built, deployed, and managed.
OWASP’s API Top 10 identifies Broken Object Level Authorization, Broken Authentication, and Resource Consumption as the most critical API vulnerabilities. Pynt’s analysis compares OWASP’s list with real-world API security trends.
Real-world breaches like those at T-Mobile and Peloton highlight the dangers of missing authentication, weak rate limiting, and exposed endpoints.
Accurate API inventory, runtime protection, and continuous security monitoring are essential for mitigating risks across modern, distributed API ecosystems.
Pynt’s shift-left dynamic scanning integrates into CI/CD pipelines, enabling early vulnerability detection with reduced false positives and minimal developer friction.
What Is API Security?
API security is the practice of protecting Application Programming Interfaces from attacks, misuse, and unauthorized access. It focuses on how APIs are built, deployed, and managed to prevent data leaks and system exposure. The goal is to keep APIs functioning safely without risking sensitive information or service integrity.
What Is API-to-API Security?
API-to-API security addresses the protection of interactions between two or more APIs. These exchanges often occur behind the scenes between internal services, making them harder to observe and control. Strong authentication, encrypted communication, and strict access policies are essential to prevent unauthorized data sharing or tampering between connected APIs.
Why Is API Security Important?
APIs are important for modern software, but without proper security, they expose critical systems and data to serious risks. Here’s why API security matters:
APIs expose sensitive data: APIs handle personal, financial, and business-critical information. If not secured, attackers can extract or manipulate this data.
They are prime attack targets: APIs are directly accessible over the internet, making them attractive entry points for attackers aiming to disrupt services or breach systems.
A single flaw can compromise entire systems: Weaknesses in one API can lead to lateral movement, privilege escalation, or complete application takeover.
Business continuity depends on them: Downtime caused by API abuse or denial-of-service attacks can lead to service disruption, lost revenue, and user frustration.
Compliance requirements demand it: Regulations like GDPR, CCPA, and HIPAA require secure handling of personal data, which includes data processed through APIs.
Growing API ecosystems increase risk: As organizations adopt microservices and integrate with third-party services, the API attack surface grows, requiring continuous monitoring and protection.
Application Security vs. API Security
While both aim to protect systems from malicious activity, application security and API security operate at different layers and require distinct approaches. Understanding their differences helps prioritize the right controls and tools based on where the risks lie. Here’s how they compare across key dimensions:
Category
Application Security
API Security
Scope
Covers the entire application stack, including front-end, back-end, and data layers.
Focused specifically on securing APIs and their interactions with other systems.
Focus Areas
Secure coding, UI logic, data validation, session handling, and overall architecture.
Endpoint authentication, access control, data flow validation, and rate limiting.
Primary Risks
SQL injection, XSS, insecure session management, and business logic flaws.
Unauthorized API access, data exposure, abuse of endpoints, and injection attacks.
Data Exposure
Typically limited to what’s shown in the user interface.
Direct access to internal services or databases, often bypassing UI restrictions.
User Authentication
Session-based authentication, typically tied to user credentials and browser sessions.
Token-based mechanisms like OAuth 2.0 or API keys with fine-grained scopes.
Threat Detection
App-level logging, behavior monitoring, and post-deployment scans.
Real-time traffic inspection, anomaly detection, and API-specific monitoring.
OWASP API Security Top 10 Risks
The OWASP API Top 10 is a widely recognized list of the most critical API security threats. Updated in 2023, it helps teams identify common weaknesses in API design and prioritize remediation efforts to reduce risk.
Here are the OWASP top 10 API vulnerabilities as of 2023, in order of severity:
Broken Object Level Authorization (BOLA): This vulnerability occurs when APIs expose endpoints that handle object identifiers, creating a wide attack surface. Attackers can exploit these endpoints by manipulating the identification of an object within a request, leading to unauthorized access to data.
Broken Authentication: This involves incorrect implementation of authentication mechanisms, allowing attackers to compromise authentication tokens or exploit flaws to assume other users' identities. This compromises the system's ability to identify users and protect API security.
Broken Object Property Level Authorization: This category combines issues related to excessive data exposure and mass assignment. It focuses on the lack of or improper authorization validation at the object property level, leading to information exposure or manipulation by unauthorized parties.
Unrestricted Resource Consumption: APIs that do not properly manage resource consumption can be vulnerable to Denial of Service attacks or incur increased operational costs due to excessive use of resources like network bandwidth, CPU, or memory.
Broken Function Level Authorization: This vulnerability arises from complex access control policies with unclear separation between administrative and regular functions. Attackers can exploit these flaws to access other users’ resources or administrative functions.
Unrestricted Access to Sensitive Business Flows: APIs that do not adequately protect business flows can be exploited in an automated manner, potentially harming business operations.
Server Side Request Forgery (SSRF): This occurs when an API fetches a remote resource without validating the user-supplied URI, allowing attackers to send requests to unexpected destinations, even through firewalls or VPNs.
Security Misconfiguration: APIs and their supporting systems often contain complex configurations. Missed configurations or failure to follow best practices can open the door to various types of attacks.
Improper Inventory Management: With APIs exposing more endpoints than traditional web applications, proper and updated documentation becomes crucial. Issues like deprecated API versions and exposed debug endpoints arise from poor inventory management.
Unsafe Consumption of APIs: Developers sometimes adopt weaker security standards for data received from third-party APIs. Attackers target these integrated third-party services to compromise the APIs indirectly.
Good to Remember
OWASP is a valuable baseline but your real API risks depend on architecture, auth design, and traffic patterns. Always validate against real usage, not just theoretical lists.
Pynt vs OWASP: Top 10 API Vulnerabilities
Explore the comparison between OWASP and Pynt API Top 10 Vulnerabilities for 2023. While both lists address common API risks like authorization flaws and misconfigurations, Pynt also identifies emerging threats such as Missing Authentication, Injection, and Local File Access.
#
OWASP API Top 10 2023
PYNT API Top 10 2023
API1
Broken Object Level Authorization (BOLA)
Missing Authentication
API2
Broken Authentication
Injection
API3
Broken Object Property Level Authorization
Broken Object Level Authorization (BOLA)
API4
Unrestricted Resource Consumption
Broken Authentication
API5
Broken Function Level Authorization
Security Misconfiguration
API6
Unrestricted Access to Sensitive Business Flows
Mass Assignment
API7
Server Side Request Forgery
Broken Function Level Authorization
API8
Security Misconfiguration
Unrestricted Resource Consumption
API9
Improper Inventory Management
Server Side Request Forgery
API10
Unsafe Consumption of APIs
Local File Access
Sources:OWASP Top 10 API Vulnerabilities, 2023, Pynt Top 10 API Security Vulnerabilities Research Report, 2023
Other Key API Security Vulnerabilities
While the OWASP API Top 10 highlights critical risks, APIs also face additional threats beyond that list. These issues often target operational gaps, business logic, and evolving technologies.
Denial of Service (DoS) attacks: Attackers overwhelm APIs with excessive requests, making them unresponsive to legitimate users. Distributed versions (DDoS) amplify the effect by using botnets to flood services at scale.
Account Takeovers (ATOs): Through credential stuffing, phishing, or social engineering, attackers gain control of legitimate accounts and use them to access APIs, make fraudulent transactions, or extract data.
Inventory denial attacks: Common in eCommerce, these attacks involve reserving or hoarding product inventory through APIs, preventing real customers from completing purchases and causing business loss.
API sprawl and shadow APIs: As organizations grow, undocumented or forgotten APIs emerge. These shadow APIs often lack security oversight, increasing the chance of exposure and attack.
AI and API security: AI-driven systems increasingly rely on APIs for input and output. If attackers manipulate the data sent through APIs, they can alter model behavior, trigger incorrect predictions, or extract proprietary training data. AI APIs also face risks like prompt injection, model inversion, and inference manipulation.
Real-World Examples of API Exploits
API vulnerabilities have led to serious data breaches across industries. These incidents highlight how poor authentication, missing access controls, or exposed endpoints can open the door to major compromise.
T-Mobile API Breach Exposed Data of 37 Million Customers
T-Mobile confirmed in 2023 that a malicious actor exploited one of its APIs to collect personal data from over 37 million customer accounts. The exposed information included names, emails, phone numbers, and billing details. The breach stemmed from an unauthenticated API that allowed access to customer data without proper rate limiting or identity checks.
Peloton API Exposed Private User Data Without Authentication
In 2021, Peloton’s public API was found to expose user account data, including location, gender, and workout metrics, even for profiles marked as private. The API failed to enforce proper authentication or authorization, which allowed anyone to query and retrieve information from millions of user accounts. The issue raised serious concerns about privacy controls and access validation across fitness platforms.
Facebook Graph API Flaw Exposed Access Tokens and Profile Data
In 2018, Facebook disclosed a vulnerability in its Graph API that allowed attackers to steal access tokens and scrape personal profile data. The issue arose from overly permissive access controls, allowing attackers to pivot from one account to another in their network. Over 50 million users were affected.
Google+ API Bug Leaked Private Profile Details to Third Parties
Google identified a critical vulnerability in its People API back in 2018 that exposed private profile fields - such as emails, occupations, and gender - to 438 third-party applications. Approximately 500,000 users had their data exposed, even though it was not marked as publicly accessible.
API Security Best Practices
Classify Data Managed by APIs
Analyze what data each API handles and assign sensitivity levels such as public, internal, or confidential.
Use specs and traffic analysis to identify data types.
Map sensitivity to controls: encryption, access restrictions, and audit logs.
Prioritize sensitive endpoints for enhanced protection.
Implement Access Control
Control who can access your APIs and what actions they are allowed to perform. Use these proven best practices:
Authenticate all requests using OAuth 2.0 or OpenID Connect to ensure users and systems are verified.
Apply Role-Based Access Control (RBAC) or Attribute-Based Access Control (ABAC) to enforce precise permissions based on roles or contextual attributes.
Use short-lived API keys or access tokens and rotate them regularly to minimize risk.
Log and audit access activity to detect excessive permissions, misconfigurations, or unusual behavior.
Security teams cannot secure what they cannot see. Building an accurate inventory of all API assets is a foundational step in protecting the API landscape. This includes every known and unknown API across environments, covering legacy services, third-party integrations, and internal tools. A reliable inventory helps identify exposed API endpoints, track the full API lifecycle, and align protection strategies with the level of data sensitivity each interface manages. Keeping this catalog current reduces blind spots and supports compliance, testing, and audit efforts.
Monitor API Activity and Audit Logs
Continuous visibility into API activity is critical for detecting suspicious behavior. Logging each API call with its associated metadata, including the endpoint accessed, the requesting user, and the time of the call, creates a valuable audit trail. These logs make it easier to uncover signs of API abuse, such as excessive call volumes or unauthorized data access attempts. By centralizing and analyzing these records - often using tools like Postman, Kong, or runtime observability platforms - security teams can improve incident response, reduce dwell time, and reinforce web API security policies in real time.
Enforce Rate Limiting and Throttling
High-frequency API traffic often signals attack attempts rather than legitimate use. Without rate limiting, malicious actors can overwhelm APIs with automated traffic or flood sensitive endpoints with repeated API calls. Throttling API access according to user roles, origin, and request type adds an important layer of control. This practice helps prevent API abuse, protects resource availability, and supports REST API security standards. Enforcing rate controls also reduces the impact of denial-of-service attacks and narrows the window for credential stuffing campaigns to succeed.
Encrypt API Requests and Responses
Encrypting the data sent to and from the APIs is an effective way to prevent unauthorized access or tampering. Encryption can be achieved through various means, such as using HTTPS for secure API communication, implementing Transport Layer Security (TLS) to encrypt the data in transit, and using encryption algorithms such as AES or RSA to encrypt the data at rest.
Encrypting API requests and responses not only protects the data from potential eavesdropping or tampering but also helps maintain the privacy and integrity of the data. By encrypting your API communication, you can ensure the security of your data, even if it is intercepted or accessed by unauthorized parties.
Aim for Continuous API Security
Securing APIs is not a one-time task. Continuous protection requires ongoing visibility, testing, and iteration to stay ahead of evolving threats and usage patterns. Adopt the following practices:
Integrate automated security tools into CI/CD pipelines to detect issues early in the development process.
Monitor API traffic and behavior in real time to catch anomalies, abuse patterns, and misuse.
Run dynamic security tests regularly to uncover logic flaws or new exposures.
Audit logs and access records frequently to track unauthorized behavior or excessive permissions.
Refine policies and controls based on new risks, changes in architecture, or threat intelligence.
Back-end APIs often serve as the core infrastructure for internal services, data pipelines, and microservice communication. While not exposed directly to end users, these APIs still face serious security risks. Misconfigured API endpoints, missing authentication layers, and unchecked API calls can lead to unauthorized access, data leakage, or full system compromise.
Securing them requires deliberate design choices and proactive controls:
Authenticate every request: Never assume back-end APIs are safe by design. Use mutual TLS, signed tokens, or identity-aware proxies to validate each call.
Limit access scopes: Apply the principle of least privilege across roles, services, and systems to reduce the chance of unauthorized data access.
Conduct regular API testing: Use automated scanners and runtime observability tools to identify logic flaws or integration errors that surface during the API lifecycle.
Encrypt all communication: Use TLS 1.2 or above for all connections to prevent interception of sensitive data, even within trusted environments.
Monitor for abuse patterns: Track anomalies in usage that may point to API abuse, excessive API calls, or privilege escalation attempts.
Tzvika Shneider
CEO, Pynt
Tzvika Shneider is a 20-year software Security industry leader with a robust background in product and software management.
Expert Tip: Boost API Security with These Actionable Steps
Implement fine-grained access control: Use a combination of role-based and attribute-based access control to ensure only authorized users have the right level of access.
Regularly update API documentation: Keep your API documentation up-to-date to avoid security gaps from deprecated or undocumented endpoints.
Conduct third-party security audits: Periodically invite external security experts to audit your APIs for an unbiased assessment.
Implement rate limiting and throttling: Protect your APIs from abuse by limiting the number of requests a client can make in a given time frame.
Use API gateways for centralized security: API gateways can enforce security policies, manage traffic, and provide analytics for better security management.
Different Types of API Security: REST API vs SOAP vs GraphQL Security
Different API architectures come with varying models of security, strengths, and risks. Comparing them side by side helps teams choose the right protocol based on their use case and security requirements.
Category
REST API Security
SOAP Security
GraphQL Security
Authentication & Authorization
Typically uses OAuth 2.0 (with adoption moving toward OAuth 2.1), API keys, or JWT. Fine-grained control depends on implementation.
Built-in support for WS-Security, including XML Signature and XML Encryption.
Relies on OAuth or token-based auth. Needs layered validation for complex queries.
Data Exposure Risk
Can overexpose data via loosely defined endpoints. Input validation is critical.
Responses are tightly structured, reducing accidental data exposure.
High risk of over-fetching or exposing nested data unless queries are restricted.
Common Threats
Injection attacks, CSRF, excessive data exposure, and broken access control.
XML-based attacks like XML injection, schema poisoning, and parser exploits.
Injection attacks, denial of service via complex queries, and introspection abuse, where attackers query the API schema to reveal available fields or operations.
Security Complexity
Moderate to high, depending on design. Requires strong endpoint governance.
High due to verbosity and strict protocol rules, but also more structured.
High. Requires careful query limiting, validation, and rate limiting.
Tooling & Standards
Widely supported by modern security tools, including API gateways and DAST scanners.
Fewer modern tools, but strong support for enterprise-grade SOAP toolkits.
Still evolving. Some tools now support GraphQL-specific security scanning.
What is API Security Management?
API security management is the process of protecting APIs from threats, ensuring they function securely while handling sensitive data. It involves implementing security measures to prevent unauthorized access, data breaches, and cyberattacks.
Key Components of API Security Management
Authentication & Authorization – Control access with OAuth 2.0, JWTs, OpenID Connect, and RBAC.
Firewalls & WAFs – Use Web Application Firewalls (WAFs) and network firewalls to block malicious traffic.
Data Encryption – Protect data in transit and at rest with TLS/SSL encryption.
Input Validation – Sanitize user input to prevent SQL injection and XSS attacks.
Rate Limiting – Restrict request frequency to prevent abuse and overload.
Monitoring & Testing – Test APIs to track API vulnerabilities and fix issues.
An API gateway helps enforce these security measures, acting as a protective layer between clients and APIs.
What Are API Security Tools and Solutions?
There are many tools and solutions available to help organizations enhance their API security. These tools provide functionalities such as vulnerability scanning, threat modeling, and security monitoring, among others.
API security tools can be broadly categorized into two types: static and dynamic:
Static API security tools, also known as Static Application Security Testing (SAST) tools, analyze the source code of your APIs to identify potential security vulnerabilities. They provide a deep understanding of your API's security posture and can be used early in the development lifecycle.
Dynamic API security tools, also known as Dynamic Application Security Testing (DAST) tools, test your APIs in a running state to identify security vulnerabilities. They simulate attacks on your APIs and monitor their behavior to detect anomalies.
There are several other important aspects of API security:
Security test automation: Integrating with API development tools and automatically testing APIs during their development stages.
CI/CD integration: Integrating API security with CI/CD pipelines and tools to ensure every iteration of API development undergoes security testing.
API discovery: Discovering shadow APIs and third-party APIs across the organization and scanning them for vulnerabilities.
Compliance: Ensuring APIs are compliant with regulations and standards
Let’s explore the key capabilities of API security solutions in more detail.
API Inventory and Discovery
Keeping an accurate API inventory is foundational to security. You cannot protect what you do not know, yet many organizations struggle to track hundreds of public and private APIs. Inventory and discovery tools provide a centralized view of all API assets, exposing endpoints, methods, and data types. As APIs evolve, these tools automatically detect changes, flag deprecated interfaces, and surface risks that might otherwise go unnoticed.
Pynt performs API inventory and discovery primarily through:
Automated Scanning: Leverages functional tests to perform an automated API security dynamic scan, identifying both documented and undocumented APIs.
Integration with API Gateways and Management Platforms: Gathers information on APIs routed through platforms like AWS API Gateway, aiding in comprehensive discovery.
Leveraging Documentation: Leverages existing API documentation, such as Swagger or OpenAPI specifications, to catalog and understand APIs.
Continuous Discovery: Regularly updates API inventory to capture new and modified endpoints, ensuring an up-to-date overview.
Categorization and Risk Assessment: Classifies APIs based on function, data sensitivity, and exposure, and evaluates potential security and compliance risks.
Managing API security posture means continuously assessing risk, identifying weaknesses, and improving defenses. Posture management tools support this process by automating key tasks:
Vulnerability scanning to detect flaws before they are exploited.
Threat modeling to simulate attack paths and prioritize risks.
Compliance monitoring to track alignment with standards such as GDPR, HIPAA, or ISO 27001.
Security trend reporting to visualize changes in posture over time.
Dashboards and alerts that surface high-priority issues for faster response.
Runtime protection secures APIs by monitoring and controlling requests and responses in real time. Since APIs expose internal application functions, this layer is essential to prevent unauthorized access and data breaches. Key mechanisms include authentication and authorization protocols like OAuth and OpenID Connect, along with defenses against injection attacks, cross-site scripting, and denial-of-service attempts. Rate limiting also plays a critical role, reducing the risk of abuse while supporting application stability.
API Security Testing
Unlike traditional UI-focused testing, API security testing targets the underlying logic and structure of APIs to uncover hidden vulnerabilities. It begins with analyzing API specifications, such as OpenAPI, to understand endpoints and data flows. From there, teams apply techniques like fuzz testing to trigger unexpected behavior, boundary value analysis to test edge cases, and penetration testing to simulate real-world attacks and identify weaknesses.
Pynt's API security testing incorporates:
Automated Dynamic Scanning: Real-time traffic analysis for immediate vulnerability detection.
Context-Aware Analysis: Tailored security assessments based on each API's unique context.
Seamless DevOps Integration: Embedding into CI/CD pipelines for continuous 'shift-left' testing.
Rapid and Efficient: Designed for quick deployment, delivering results in a short amount of time.
Minimized False Positives: Advanced algorithms to reduce incorrect threat identifications.
Developer-Friendly: Easy integration, ensuring a smooth user experience for developers.
API governance is an overarching component of API security. It involves defining and implementing policies, procedures, and standards for API usage and management. This not only helps maintain API security but also ensures the APIs are used effectively and efficiently, delivering maximum value to the organization.
API governance policies typically address several key areas of API usage:
Authentication and authorization to control who can access what
Rate limiting to prevent abuse and ensure fair usage
Data privacy to protect sensitive information and comply with regulations
Error handling to ensure consistent and secure responses
Enforcing these policies requires supporting mechanisms, including:
Logging and auditing to track API activity and detect anomalies
API gateways to monitor traffic and enforce rules at runtime
API management platforms to centralize control and maintain policy consistency
Securing APIs Early: Pynt’s Shift-Left Approach
Pynt's approach to API security emphasizes a 'shift-left' methodology, focusing on early discovery and resolution of vulnerabilities. This proactive stance in the software development life cycle allows for:
Early Detection: Identifying API vulnerabilities early in the development process reduces potential security risks.
Seamless Integration: Facilitating easy integration with existing development tools and pipelines, enhancing developer productivity without compromising security.
Comprehensive API Discovery: Automated discovery of APIs, ensuring complete visibility from development to production, is crucial for identifying shadow APIs and other hidden risks.
These aspects collectively enhance the overall security posture by addressing API vulnerabilities at their inception, rather than as an afterthought.
APIs are at the core of modern digital services, but their expanding complexity demands stronger security measures. Misconfigurations, weak authentication, and unmonitored endpoints can expose systems to serious threats that affect data integrity, service availability, and customer trust.
Organizations can strengthen their API defenses by applying proven security best practices, maintaining a complete and accurate API inventory, and using specialized tools for monitoring, testing, and access control. Securing APIs is not a one-time task but an ongoing effort that must evolve alongside the technologies and threats shaping the software ecosystem. As APIs continue to power AI systems, mobile applications, and cross-platform integrations, protecting them is more than a technical necessity. It is a foundational step toward building lasting digital trust and ensuring resilience in a constantly shifting threat landscape.
FAQs
What are API security standards?
API security standards guide how APIs should be secured across their lifecycle, from design to deprecation. Key standards include:
OWASP API Security Top 10: Helps identify and prioritize common API security risks
OAuth 2.0 / 2.1 and OpenID Connect: For secure authorization and identity federation
TLS 1.2+: Ensures encrypted communication between clients and servers
NIST SP 800-53 and ISO/IEC 27001: Establish broad security and compliance frameworks
OpenAPI Specification (OAS): Can define security requirements directly within API contracts
What is a zombie API?
A zombie API is an outdated or deprecated API endpoint that remains publicly accessible despite no longer being maintained or documented. These forgotten interfaces often arise from microservice sprawl or incomplete decommissioning in CI/CD pipelines. Since they typically escape version control and security testing, they become high-risk targets for exploitation.
How to secure an API without authentication?
Securing an API without authentication is only appropriate for low-risk scenarios, such as open data feeds or internal systems that do not handle sensitive information. In these cases, security relies on layered compensating controls. Rate limiting, throttling, and IP filtering can restrict traffic volume and origin, while limiting endpoints to read-only access ensures that no data can be modified. Input validation and schema enforcement help prevent injection and misuse.
Logging every request adds visibility into usage patterns and supports anomaly detection. Finally, using API keys or allow lists—even without full authentication—can help control access in a basic but effective way.
What is the API security lifecycle?
The API security lifecycle involves securing APIs across all phases of development and use:
Design: Define access scopes, threat models, and data classification
Deployment: Enforce authentication, authorization, encryption, and rate limiting
Monitoring: Track usage patterns, detect anomalies, and log traffic for analysis
Retirement: Revoke access, decommission unused endpoints, and update the API inventory
How do you protect an API with SSL?
APIs are protected using TLS (the modern version of SSL) through the following:
Enforce HTTPS and disable outdated protocols like TLS 1.0 or SSLv3
Use valid TLS 1.2 or 1.3 certificates issued by a trusted certificate authority
Enable HSTS headers to prevent downgrade attacks
Rotate, revoke, and renew certificates on a scheduled basis
In sensitive environments, implement mutual TLS (mTLS) for client-server authentication
How do API gateways handle security internally?
API gateways serve as centralized points of enforcement for API traffic. They help secure APIs by:
Authenticating users via OAuth 2.0, JWT tokens, or API key
Enforcing rate limits, quotas, and IP restrictions
Validating request schemas and rejecting malformed payloads
Applying access control policies to route traffic securely
Logging and analyzing request data for threat detection and alerting
Optionally integrating with WAFs for attack pattern recognition (e.g., SQLi, XSS)
How are APIs encrypted?
APIs use encryption to protect data both in transit and at rest:
In transit: Secured via TLS 1.2 or 1.3, which encrypts communication between client and server
At rest: Protected using encryption methods such as AES-256 at the disk, database, or application layer
What is API security scanning?
API security scanning is the process of testing APIs to identify security flaws throughout their lifecycle. It combines early-stage testing during development with continuous monitoring in production environments.
One method focuses on shift-left testing, where simulated attacks are used during the build phase to identify issues such as broken authentication, excessive data exposure, or insecure logic. The other involves real-time scanning of live API traffic to detect threats such as abuse patterns, unauthorized access attempts, or anomalous behavior.
Together, these approaches reduce risk, prevent data leaks, and help ensure APIs remain secure from development through deployment and beyond.
See Additional Guides on Key Application Security Topics
Together with our content partners, we have authored in-depth guides on several other topics that can also be useful as you explore the world of application security.