API discovery refers to identifying and cataloging all the Application Programming Interfaces (APIs) available within an organization's ecosystem or across the web. This includes internal APIs the organization developed for its use and external APIs provided by third-party vendors or partners.

API discovery involves several steps:

Identification: This step involves identifying all potential sources of APIs within the organization, such as software applications, databases, services, or cloud platforms. External sources, including public API directories, developer portals, and API marketplaces, may be scanned to discover third-party APIs relevant to the organization's needs.

Scanning and Crawling: Once potential sources are identified, automated tools or scripts may scan and crawl these sources to extract information about available APIs. This includes analyzing web pages, documentation, code repositories, and network traffic to identify endpoints, methods, parameters, and other API specifications.

Cataloging and Documentation: Discovered APIs are cataloged and documented to create a comprehensive inventory. This includes capturing metadata such as API endpoints, descriptions, versions, authentication mechanisms, supported protocols, data formats, usage policies, and contact information for API owners or maintainers.

Classification and Tagging: APIs are classified and tagged based on various criteria, such as functionality, purpose, industry, or security requirements. This helps organize the API inventory and facilitates searching, filtering, and categorizing APIs based on specific criteria or use cases.

Analysis and Validation: Discovered APIs are analyzed and validated to ensure their accuracy, completeness, and relevance to the organization's needs. This may involve testing API endpoints, verifying authentication mechanisms, assessing data security practices, and evaluating compliance with industry standards or regulations.

Monitoring and Maintenance: API discovery is an ongoing process that requires regular monitoring and maintenance to keep the API inventory up-to-date. Organizations need to continuously update their API inventory and documentation accordingly as new APIs are developed, deprecated, or retired.

API discovery is essential for organizations to effectively manage their API ecosystems, facilitate collaboration between development teams, enable integration with third-party services, and ensure compliance with security and regulatory requirements. By maintaining a comprehensive inventory of APIs and their specifications, organizations can streamline API usage, reduce redundancy, improve security, and enhance the overall efficiency of their software development processes.

An all-in-one external attack surface management (EASM), digital risk protection (DRP), and security ratings solution like ThreatNG with a Domain Intelligence Module can significantly assist an organization in API discovery. Here's how it can help and integrate with complementary security solutions:

Identification of API Endpoints: ThreatNG's deep investigative DNS, subdomain, certificate, and IP capabilities enable the identification of all potential sources of APIs within an organization's external attack surface. By scanning and analyzing DNS records, certificates, and IP addresses, ThreatNG can identify web applications and services that expose APIs. For example, ThreatNG discovers a new subdomain associated with the organization's domain. Further analysis reveals that this subdomain hosts an API endpoint previously unknown to the organization.

API and Application Discovery: ThreatNG's API and application discovery features facilitate identifying and cataloging APIs within an organization's ecosystem. By scanning web applications and services for API endpoints, ThreatNG can create a comprehensive inventory of APIs, including metadata such as endpoints, descriptions, versions, and authentication mechanisms. Example: ThreatNG identifies APIs exposed by internal web applications and cloud services used within the organization. It catalogs these APIs and provides detailed documentation for developers and security teams.

Technology Stack Identification: ThreatNG's technology stack identification capabilities enable organizations to identify APIs' underlying technologies and frameworks. ThreatNG can determine the technology stack of web applications and services hosting APIs by analyzing HTTP responses, server headers, and other indicators. Example: ThreatNG identifies that an API is built using a specific version of a framework with security vulnerabilities. This information helps the organization prioritize patching and remediation efforts.

Assessment for Web Application Hijack Susceptibility: ThreatNG's assessment for web application hijack susceptibility can identify APIs vulnerable to hijacking attacks, such as session fixation, cross-site scripting (XSS), or cross-site request forgery (CSRF). Organizations can proactively identify and remediate these vulnerabilities to secure their APIs against common web application security threats. Example: ThreatNG detects an API endpoint vulnerable to CSRF attacks due to missing anti-CSRF tokens. The organization implements proper CSRF protection mechanisms to mitigate the risk.

Integration with Complementary Security Solutions:

API Security Gateways: ThreatNG can integrate with API security gateways to provide real-time visibility into API endpoints and associated risks. API security gateways can use ThreatNG's intelligence to enforce security policies, inspect API traffic, and block malicious requests.

Web Application Firewalls (WAFs): ThreatNG's API discovery capabilities can complement WAFs by providing additional visibility into APIs and potential attack vectors. WAFs can use ThreatNG's intelligence to create custom rulesets to protect APIs against common web application attacks.

API Management Platforms: ThreatNG's API discovery and assessment capabilities can integrate with API management platforms to provide comprehensive API lifecycle management. API management platforms can use ThreatNG's intelligence to automate API discovery, documentation, versioning, and retirement processes.

By leveraging ThreatNG alongside complementary security solutions, organizations can establish a comprehensive approach to API discovery and security. This integrated strategy enables organizations to identify, catalog, and secure APIs within their external attack surface, reducing the risk of security breaches and data leaks.