What Is API Security? A Comprehensive Guide to API Security

What’s API Safety?

API safety covers all the safety instruments, processes, and controls concerned in defending techniques, knowledge, and organizations from threats concentrating on APIs—utility programming interfaces. In contrast to graphical person interfaces, APIs are meant for automated knowledge alternate with exterior techniques and between inner utility elements. When taking a look at APIs as an extension of the seen utility assault floor, three core areas of API safety are essential for securing functions:

• API discovery: By figuring out the interior and exterior APIs they’re utilizing and exposing, organizations can construct a extra full image of their assault floor. Well-liked API discovery strategies embrace crawling for specification information and endpoints, integrating with API administration instruments, and monitoring API site visitors.
• API safety testing: As soon as API endpoints are identified, they are often examined for vulnerabilities manually and thru automated scanning. Whereas guide API testing was the norm, the massive numbers of endpoints and parameters concerned imply that superior dynamic utility safety testing (DAST) instruments are actually generally used to automate a lot of the testing.
• API safety: Most organizations will use an API gateway to route API site visitors via a single system that places a number of safety measures between an API and potential attackers. Safety options can embrace load balancing, fee limiting, and an online utility firewall (WAF) to supply real-time API site visitors filtering. 

API safety is a broad area that covers different areas and power classes as nicely. To call simply two, API posture administration (additionally known as classification or categorization) entails labeling API endpoints to assist with remediation for brand spanking new vulnerabilities. One other widespread concern and a significant a part of API safety methods is API entry management, which entails defining particular person and utility entry rights to APIs to offer safety extra management over what’s accessed and uncovered.

Why is API safety vital?

APIs present a much less apparent manner for attackers to entry delicate data from functions. As an alternative of breaking in via the person interface, menace actors typically favor to search for an unprotected facet door, making APIs a first-rate goal and a supply of main knowledge breaches, together with many who have uncovered private knowledge. Contemplating the thousands and thousands of IoT (Web of Issues) gadgets that use internet APIs to obtain instructions, return knowledge, and carry out operations, API assaults may also enable malicious hackers to compromise bodily safety measures and exploit insecure internet-facing gadgets as entry factors to pivot into inner techniques.

There are not less than 5 high-level the explanation why API safety has turn out to be so vital for organizations:

• Defending delicate knowledge: APIs typically serve and course of private, monetary, and enterprise knowledge. A breach can expose delicate data, together with private knowledge, resulting in monetary losses, reputational injury, and regulatory penalties for firms whereas additionally placing people liable to identification theft.
• Securing an elevated utility assault floor: APIs are designed to reveal utility performance and knowledge to the skin world. With out correct safety, API endpoints initially meant to be used by official functions can turn out to be entry factors for attackers.
• Mitigating superior and high-intensity assaults: As a result of APIs are designed for automated entry, they’re particularly focused in lots of high-intensity utility assaults, from injection assaults and massed credential stuffing to distributed denial of service (DDoS). Robust API safety measures can stop or mitigate these doubtlessly devastating assaults.
• Guaranteeing regulatory compliance: Knowledge safety rules equivalent to PCI DSS, HIPAA, and GDPR mandate sturdy safety measures for all techniques dealing with delicate data. This makes implementing and demonstrating stable API safety a significant step to make sure compliance.
• Sustaining enterprise continuity: Relying on the appliance structure, APIs can straight assist or carry out important enterprise operations throughout a number of techniques. Because of this, an API safety breach can pose a far higher menace to enterprise continuity than different assault avenues, with the potential to severely disrupt providers, influence income, and erode buyer belief.

What’s the distinction between API safety and utility safety?

API safety is a subset of general utility safety and is important for shielding trendy functions that depend on internet providers and APIs for knowledge alternate with techniques and customers. Purposes designed utilizing microservice architectures go a step additional and are fully constructed from providers that depend on API calls not just for exterior communications but additionally for inner knowledge interchange.

One vital distinction is that API site visitors is sort of fully automated, permitting for request volumes that you’d not often get from guide person interactions with an online utility GUI. This enforces totally different necessities in comparison with “common” utility safety and makes intensive automation a non-negotiable facet of any efficient API safety program. This goes doubly for backend APIs, the place many techniques, providers, and functions can depend on the identical API to function—together with most cell functions.

What’s the distinction between REST, SOAP, and GraphQL API safety?

An API might be any option to programmatically entry utility knowledge and performance, together with fully customized implementations, however most organizations are likely to go together with one in every of a number of widespread API varieties (so as of recognition primarily based on a 2023 report): REST, SOAP, or GraphQL. Whereas the network-level safety measures will rely extra on utility structure than API kind, application-level API safety differs considerably throughout API architectures.

REST API safety

REST APIs are by far the commonest API kind, utilized in over 85% of organizations that work with APIs. REST (REpresentational State Switch) is just not a strict protocol or format however an architectural model for constructing internet functions and providers. With REST, HTTP protocol strategies are used as operation varieties, and JSON is the commonest knowledge format.

As a result of every operation uncovered by the API wants its personal endpoint and URL, REST APIs are main contributors to the general assault floor, particularly since REST requests might be very predictable. When a brand new API spec is revealed, the previous and new variations sometimes coexist for a time to keep up compatibility for current API shoppers. Forgotten APIs which can be left in manufacturing indefinitely are a standard assault vector in REST API safety, generally requiring solely a change from v2 to v1 within the URL to entry a much less safe model of a manufacturing API.

SOAP API safety

SOAP (Easy Object Entry Protocol) was the “authentic” internet API format and stays in use right now, particularly in enterprise functions, although it’s much less widespread than REST. In contrast to the loosely-defined REST model, requests within the XML-based SOAP API kind must strictly conform to a predefined schema, making them much less handy for easy operations and particularly for frequent adjustments throughout fast growth.

Being particularly designed as an enterprise API format, SOAP is usually thought-about safer than REST, particularly because it consists of some built-in options for error dealing with and encryption. SOAP requests should additionally strictly observe the XML schema outlined for the API, making them tougher for attackers to spoof or imitate (although additionally tougher to check).

GraphQL API safety

The place REST and SOAP are general-purpose API varieties, GraphQL is just not a lot an API format as a specialised knowledge question and manipulation language for database entry APIs. Though a relative newcomer in comparison with REST and SOAP, it’s shortly gaining reputation, being utilized by as much as 30% of API builders. 

As an alternative of a number of endpoints per API like REST, GraphQL often solely makes use of a single endpoint to obtain queries and return knowledge, which may simplify site visitors routing and safety testing. It additionally has some built-in options for validation and kind checking. On the similar time, GraphQL safety comes with its personal challenges, not the least of that are second-order vulnerabilities. It’s widespread to implement a GraphQL layer to unify current REST APIs, making it an oblique goal for injection assaults in opposition to these underlying APIs.

What are the primary forms of API vulnerabilities?

Whereas APIs are sometimes talked about as separate entities, the very title “utility programming interface” is a reminder they’re solely an intermediate layer of entry to some underlying system or utility. Any dialogue of API vulnerabilities wants to think about two ranges of safety:

• Vulnerabilities within the API: The interface ought to solely go legitimate and licensed requests to the backend utility. If attackers handle to compromise API protections, they will bypass or break authorization, get hold of API entry, and make malicious requests. Widespread API vulnerabilities embrace weak or unprotected API keys, damaged authentication, failure to implement HTTPS for all API site visitors, and insufficient fee limiting that permits for DDoS (Distributed Denial of Service) assaults.
• Vulnerabilities within the backend utility: Attackers deal with API endpoints as merely one other utility entry level to probe and assault. After bypassing or overcoming API-level protections, malicious hackers can goal an unlimited array of safety vulnerabilities via API calls, together with widespread injection assaults like SQL injection, command injection, and cross-site scripting (XSS). Within the API context, SSRF (server-side request forgery) vulnerabilities might be particularly harmful by permitting entry to inner techniques that weren’t anticipated to be publicly out there.

OWASP API Prime 10 safety dangers

OWASP (the Open Net Software Safety Undertaking) maintains a number of high 10 lists associated to internet utility safety, with one of many newer being the API Safety Prime 10. In case your functions expose API endpoints, it is advisable incorporate API-related safety dangers into your general cybersecurity technique. Itemizing probably the most impactful dangers is the acknowledged objective of the API Safety Prime 10, so the record ought to be handled as an help to safe design for API growth and API safety controls, not as an specific API vulnerability guidelines.

OWASP API Prime 10 for 2023

• API1:2023 Damaged Object-Degree Authorization
• API2:2023 Damaged Authentication
• API3:2023 Damaged Object Property-Degree Authorization
• API4:2023 Unrestricted Useful resource Consumption
• API5:2023 Damaged Perform-Degree Authorization
• API6:2023 Unrestricted Entry to Delicate Enterprise Flows
• API7:2023 Server-Aspect Request Forgery
• API8:2023 Safety Misconfiguration
• API9:2023 Improper Stock Administration
• API10:2023 Unsafe Consumption of APIs

As with all OWASP high 10 lists, it’s helpful to search for broader strategic themes. At a excessive stage, the foremost API safety dangers might be grouped into 5 broad classes:

• Entry authorization and person authentication: Most API-related breaches end result from unauthorized entry on the stage of objects (damaged object-level authorization, aka BOLA), object properties, or utility capabilities (damaged function-level authorization). Carefully associated are authentication failures, with damaged authentication mechanisms placing apps liable to delicate knowledge publicity by way of unauthenticated API entry.
• Entry management and limiting: APIs are designed for automated use, so all API entry must be rigorously managed to regulate safety threats associated to malicious API requests despatched in bulk. Dangers embrace server useful resource exhaustion, mass knowledge exfiltration, and abusing API performance via brute-force enumeration and related strategies.
• API stock administration: If you happen to unknowingly nonetheless expose previous variations of endpoints or complete APIs, you’re giving menace actors a simple place to begin and rising the chance of unauthorized entry. One of the best observe is to know, monitor, and doc all of your APIs and endpoints, whether or not non-public or public, although few organizations can declare to do that efficiently.
• Safety misconfigurations: Lacking or misconfigured safety headers and different configuration-related safety points are a standard supply of threat for internet functions and APIs alike. They’re particularly harmful as a result of they will depart APIs susceptible at runtime even when the code itself seems to be safe.
• Unfixed utility vulnerabilities: APIs are simply one other entry level for attackers, so API assaults are sometimes a part of an even bigger utility assault in opposition to particular safety flaws. Whereas many widespread vulnerabilities might be focused by way of APIs, SSRF vulnerabilities are particularly helpful for attackers as they will flip an API right into a URL manipulation device for accessing distant sources.

API safety testing with DAST

Automated dynamic utility safety testing instruments are the pure selection for probing the whole assault floor of an utility, each API and GUI—however only a few internet vulnerability scanners are mature and correct sufficient to soundly run the 1000’s of safety checks required and return helpful outcomes.

As the primary DAST vendor to construct API scanning into its merchandise, Invicti continues to steer the business within the accuracy, protection, and automation of internet utility and API vulnerability scanning. The Invicti platform comes with a number of options and capabilities for automated API safety testing, together with:

• REST, SOAP, GraphQL, and gRPC API definition assist for importing and testing
• Multi-faceted endpoint and definition discovery (for REST APIs)
• Absolutely automated authenticated vulnerability scanning masking internet apps and APIs (together with OAuth single sign-on environments)
• Centralized visibility of API endpoints and vulnerabilities as a part of the general internet utility assault floor
• Computerized URL rewriting to enumerate and take a look at predictable endpoints found throughout crawling
• A whole lot of mature safety checks to soundly and precisely detect safety points in web sites, functions, and APIs

See Invicti API Safety in motion

API safety finest practices

Defining and implementing efficient API safety insurance policies and controls ought to be an integral a part of your wider utility safety program. On the similar time, some safety measures are API-specific, so listed below are some key methods to ensure that API safety necessities are by no means missed or underestimated:

• Outline an API safety technique. This could embrace insurance policies and controls for API discovery, safety testing, stock, administration, and safety.
• For any massive manufacturing APIs, use confirmed safety options to supply runtime safety. This could cowl entry management in addition to automated site visitors filtering and throttling.
• Centralize and implement API administration to assist builders and safety groups alike maintain monitor of lively APIs and present specification variations. This could embrace a standardized, automated course of for API enrollment and decommissioning.
• Work with engineering groups to outline safe coding requirements for API design and growth. These ought to embrace permitted architectures, design patterns, and safety controls.
• By no means assume with out testing that API person authentication shall be dealt with by one other system. Following such zero-trust rules turns into particularly vital with multi-layered APIs.
• Incorporate APIs right into a constant and steady discovery and safety testing course of for internet property. This helps normalize API safety as a subset of utility safety and combine it into the software program growth lifecycle.
• Guarantee your safe coding practices embrace enter validation and sanitization. That is particularly vital for APIs, the place defending object identifiers is essential to forestall IDOR vulnerabilities.
• Construct API safety testing into your DevOps pipelines by integrating utility and API discovery and safety testing with current growth instruments and problem trackers.

Constructing a steady internet utility and API safety course of

In comparison with utility safety testing, the place totally different testing methodologies can be utilized at totally different levels of growth, and plenty of safety points might be caught already on the supply code stage via static utility safety testing (SAST aka static evaluation), nearly all of API safety testing must be performed dynamically. It’s because you typically gained’t have direct entry to the underlying utility or system (nor its supply code), and even in case you did, you continue to want to check for runtime vulnerabilities, whether or not brought on by misconfigurations or complicated interactions between techniques in manufacturing.

A DAST-centric course of and toolset for built-in utility and API safety testing is an efficient option to systematically discover and remediate safety weaknesses earlier than they are often exploited by malicious actors. To make this work in observe requires a DAST answer that maximizes protection for discovery and testing, can take a look at throughout all widespread internet app and API applied sciences, and integrates deeply into the software program growth lifecycle (SDLC). Relying in your DevOps workflow, it also needs to have the ability to run scans routinely in a steady course of: at predefined factors within the growth pipeline (sometimes for brand spanking new builds), on a business-specific schedule in manufacturing, or each.

To learn the way this may be performed utilizing an built-in DAST-centric AppSec platform, learn the Invicti white paper Safety on the Velocity of Software program: DAST within the SDLC.