Hi there! With businesses relying on APIs now more than ever to unlock innovation, the spotlight inevitably turns to API security. As an application security professional, I‘m sure you appreciate both the pivotal role APIs play and the risks insecure ones pose.
In this comprehensive guide, we‘ll get to the bottom of the how and why of API security – so you can scope your exposure and take positive steps to safeguard your infrastructure.
The API Economy: A Double-Edged Sword
Let‘s first acknowledge the immense value APIs unlock for enterprises in the digital era:
- Agility – Streamlined integrations between apps, services and partners
- Efficiency – Automation and computational offloading to optimized cloud services
- Innovation – Ability to quickly turn ideas into products with minimum overhead
- Revenue – APIs directly used by customers or monetized through developer ecosystems
Gartner predicts that by 2025, more than 50% of organizations will monetize data via APIs and related data services. That‘s massive!
However, this API-driven growth comes with its fair share of chaos and complexity. Over 63% of organizations have more APIs than they can effectively track and manage.
And herein lies a paradox – APIs deliver immense business value but also open up attack vectors that are hard to monitor and secure. Just ask the likes of Facebook or Peloton!
Fact: According to Salt Security, 60% of APIs remain unprotected. Hundreds of API breaches occur each year across industries.
So do you know how exposed your APIs are or what levels of access they grant externally? Most likely the answer is "I don‘t know for sure" or perhaps that‘s a question you haven‘t even asked yet. If so, it‘s time we change that!
API Security Risks: By the Numbers
Before exploring how to secure APIs, it‘s important we acknowledge the actual risks:
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The average API breach impacts 5.4 million records according to a 2022 report titled "Too Much of a Good Thing? Enterprise API Adoption Trends and Associated Risks"
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IBM estimates the average cost of a data breach stands at $4.35 million – a considerable sum driven largely by APIs.
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Research shows only 26% of developers claim to be following API security best practices. That‘s rather worrying given they design the very apps and microservices putting your data at risk.
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Recent findings estimate there are 2.7 API abuses per second – indicating elevated threats.
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High profile examples like the 2016 Uber breach where hackers using stolen internal keys accessed driver names, license details and more of 50 million drivers show that even tech unicorns grapple with API security.
The risks are real – for both data andbottom lines. Now let‘s get to grips with how to secure your APIs.
An API Security Program Built on Standards
They say you can‘t manage what you can‘t measure. When dealing with something as fluid as APIs in a complex modern enterprise, having frameworks and standards to orient governance is vital.
OWASP API Security Top 10
The OWASP API Security Project is the industry authority when it comes to API risk awareness.
OWASP API Security Top 10, Source: owasp.org
Getting familiar with these top 10 risks is a prerequisite for pragmatic API security to understand actual vulnerabilities plaguing real-world infrastructure.
We won‘t delve into each one here but I highly recommend reviewing the detailed OWASP API Security Top 10 Cheat Sheet for risk scenarios, security pointers and remediation advice.
ISO Standards
Global ISO standards like ISO 27034 and 29151 establish a common framework and vocabulary for implementing holistic application security controls inclusive of APIs.
Certifications like the ISO 27001 Lead Auditor also validate expertise in designing and governing security management systems – a key capability for complex API ecosystems.
CSA STAR
The Cloud Security Alliance (CSA) publishes consensus assessments like the Security Trust and Assurance Registry (STAR) that create transparency on cloud provider security capabilities – vital when APIs tap cloud-hosted services.
An API Security Model for the Real World
Now that we understand key risks and relevant standards – let‘s put this into practice with an actionable model tailored for the world of constantly evolving and expanding APIs:
Discover – Invest in API discovery to map assets, endpoints and data flows – on prem, cloud or partner exposures.
Define – Classify API business criticality, data sensitivity and access requirements.
Govern – Establish data governance policies reflecting security, compliance and privacy needs.
Develop – Embed secure coding practices matching API risk profile right through SDLC.
Analyze – Perform dynamic scanning and behavioral analytics to detect anomalies.
Enforce – Protect running APIs via authentication, data masking, rate limiting.
Audit – Validate controls efficacy through continuous security testing.
Orchestrate – Connect workflows across developers, infrastructure and security tools.
Evolve – Use learnings to strengthen controls and deliver API-centric protection.
Note this aligns data protection to API flows, balances enablement with controls, incentivizes secure innovation by design, and crucially – orchestrates disparate systems to maximize ROI of investments.
With this model in mind, let‘s dig deeper into key mechanisms for locking down API access.
Authentication: Who Can Access What
Authentication establishes user or application identity as a precursor to authorizing access. Flawed authentication enables unauthorized API usage, so getting it right is key.
API Keys
In this simple approach, applications pass API keys – which act like static passwords – with requests. It‘s easy to implement but insecure since compromised API keys grant full rather than granular access.
OAuth 2.0
OAuth 2.0 delegates authentication to trusted identity providers using short-lived access tokens. Various grants cater to web, mobile, JavaScript and server-based apps. It also offers features like scopes for fine-grained authorization.
OAuth 2.0 simplifies secure access delegation, Source: auth0.com
OpenID Connect (OIDC)
An extension of OAuth 2.0, OIDC adds an identity layer providing verification of users alongside resource access. It facilitates single sign-on (SSO), allowing tap-in authentication to multiple apps and APIs.
SAML
SAML or Security Assertion Markup Language passes authentication and authorization details between identity providers and service providers. SAML binds user identities and attributes over a federated single sign-on environment.
Mutual TLS
Also known as certificate-based mutual authentication, MTSSL uses client-side and server-side certificates to establish identity in both directions. It offers a higher degree of assurance and avoids transmitting credentials over the wire.
Choosing the right protocols and integrations between identity management systems, VPNs, SIEMs and APIM solutions is key to avoiding account takeovers or stolen credentials.
Authorization: Who Can Do What
Once authenticated, requests should only be allowed predetermined actions – realized through authorization policies:
- Role based – Certain user roles can access assigned API resources
- Rule based – Business policies determine permissible operations
- Context based – Various factors like strength of authentication, device posture, geolocation etc. affect access
- Time bound – Access restricted to specific periods to limit exposure
- Rate limited – Slow down excessive usage to prevent denial of service
These controls limit data and functions exposure on a need to know basis, containing impact of compromised credentials.
Secure API Development
The most crucial frontline for API security are the developers actually building them. Here are leading practices to embed preventative controls:
Threat Modeling
Envisage trust boundaries, data flows, assets, entry points and access requirements early in design. Identify potential threats like injections, protocol flaws etc. to inform controls.
Static Analysis
SAST or Static Application Security Testing inspects code for errors and verification against secure coding checklists beginning from commit stages.
Dynamic Analysis
DAST scans like fuzzing attack running APIs by manipulating parameters to uncover logical issues and surface vulnerabilities like information disclosure or injection flaws.
Pen Testing
White box testing through simulated attacks uncovers risks early in SDLC to fix cheaper. Adversarial mindset balanced with production stability avoids oversights.
Pipeline Integrations
Tools like SAST, DAST etc. should run on every code change to shift security left. Infrastructure-as-code templates also help set up environments securely.
Operational Enablement
Logging, monitoring and analytical capabilities assist troubleshooting while feedback loops drive continuous controls improvement aligned to API risk climate.
Partner Assurance
Extend governance to third parties building or consuming APIs to maintain consistency in security posture – specially relevant for open banking or connected ecosystems.
API Protection: Shielding Production APIs
Protecting production APIs requires ongoing, adaptive safeguards – not just point in time testing:
Multilayered API Protection (source: Akana)
Perimeter Defenses
Web application firewalls (WAF) filter attempted attacks using signatures and behavioral analysis at the edge before they reach APIs.
Identity & Access
Multi-factor authentication (MFA), identity federation, OAuth tokens help authenticate verified users and apps only.
Rate Limiting
Setting request thresholds per endpoint or user mitigates brute force and DDoS. Load shedding allocates capacity during spikes.
Input Validation
Whitelist allowlists, parameterized queries, binding checks and sanitization validate inputs.
Encryption
Transport layer security (TLS) establishes secure channels while field or database encryption protects data at rest.
Monitoring
Audit trails tracking access provide visibility for security analytics to detect threats and guide policy evolution. SIEM integration centralizes monitoring.
The layers work in tandem – establishing robust security zones to protect API landscapes end to end.
API Security Testing: Staying A Step Ahead
Hoping nothing will go wrong is not smart philosophy in our line of work! Instead rigorously test using multiple tools and techniques:
SAST/DAST/IAST
Catch coding errors, logic flaws or runtime weaknesses early through static, dynamic and interactive application testing tools.
Fuzzing
Manipulate unexpected inputs via mutation based testing that uncovers crashes indicating potential serious vulnerabilities.
Offensive Security
Hacker powered penetration testing is indispensable to truly evaluate system compromises or data breaches bypassing controls through combinations of exploits.
Breach Simulation
Actually stage safe attacks mimicking adversary tradecraft on production infrastructure to bolster readiness and controls.
Bug Bounties
Crowdsourced responsible disclosure programs incentivize researchers to find flaws not detected earlier – great for consuming public APIs.
Platform Integrity
Cloud assurances like SOC reports, API trust scores etc. validate security health of external services used by APIs.
Testing is your radar revealing the gaps bad actors strive to exploit. Keep it running continuously across the scope!
API Security Solutions Landscape
While custom coding vigilance offers a baseline, commercial and open source API security platforms greatly simplify tackling common threats at scale:
API Gateways
Tools like Microsoft Azure API Management, Mulesoft, Kong, Tyk and more help manage cross cutting aspects like authentication, access control, throttling, caching, transformations etc.
WAFs
Top application security vendors like F5, Akamai, Imperva etc. filter attacks targeting web facing APIs based on signatures, learning, and positive security models.
CI/CD Integrations
SAST solutions like Checkmarx, Veracode, SonarQube etc. plus DAST tools like OWASP ZAP and Burp Suite can be automated across build and release workflows.
API Testing Platforms
Specialized suites like Postman, Runscope, SoapUI focus on functional and security testing of API interfaces.
API Security Specialists
Vendors like Salt Security, Noname Security, Traceable etc. take API centric approaches covering discovery, posture management and runtime protection.
Choosing the right tools – open source or commercial – and strategically integrating them into your SDLC, infrastructure and operations is key to balancing productivity and protection for your APIs.
Take Control of Your API Security Posture
Phew, that was quite the whirlwind tour of the what, why and how of API security!
Here are the key takeaways as you formulate your API protection roadmap:
- Discover your API assets – exposure often exceeds documented interfaces
- Map policies to data flows based on risk appetite
- Adopt API security standards into governance frameworks
- Incentivize secure API design for developers while enabling rapid innovation
- Protect running APIs through layered controls and continuous testing
- Orchestrate existing investments into API specific defenses
I hope this guide has armed you with knowledge and a structured game plan so you can take decisive actions towards comprehensive API protection. Secure APIs will turbo-charge digital transformation while keeping the bad guys out!
Do let me know if you have any other questions. I‘m always happy to help colleagues strengthen cyber resilience.
