Application programming interfaces, or APIs, are the backbone of modern software, powering everything from web applications to mobile platforms and microservices. But with that central role comes risk. APIs are prime targets for attackers looking to exploit vulnerabilities and gain access to sensitive data or systems. Following proven API security best practices, and integrating advanced security testing tools like Invicti’s DAST-first application security platform, is essential to protecting your digital assets.

Foundational practices for securing an API

Use strong authentication

Enforce authentication mechanisms such as OAuth 2.0, API keys, or JWTs to ensure only legitimate users and systems can access your APIs. Avoid relying on shared secrets or basic authentication.

Invicti supports authenticated API scanning, enabling it to test behind login-protected endpoints while maintaining session integrity throughout the scan.

Enforce authorization and access controls

Authentication proves identity; authorization controls what that identity can access. Use role-based access control (RBAC) or attribute-based access control (ABAC) to prevent privilege escalation or unauthorized data access.

With Invicti, you can scan (for supported configurations) APIs as different user roles to ensure access controls are properly enforced across all endpoints.

Encrypt data in transit

All API communications should use TLS encryption (HTTPS) to protect data from interception. Never transmit sensitive information over unencrypted channels.

Invicti identifies insecure HTTP endpoints and flags them as high-risk, helping you enforce encryption best practices.

Advanced best practices in API security

Implement rate limiting

Rate limiting helps prevent brute-force attacks, denial-of-service attempts, and abuse of public-facing APIs. It also reduces the attack surface by limiting how often an endpoint can be accessed.

While Invicti focuses on vulnerability discovery rather than performance testing, it may help identify endpoints that appear unprotected by rate limits, especially when multiple automated requests yield no errors or throttling indicators.

Validate and sanitize input

Never trust user input. APIs should validate data types, ranges, and formats—and sanitize input to block injection attacks.

Invicti’s scanning engine is purpose-built to test input validation by attempting SQL injection, command injection, and other input-based exploits. If input isn’t properly handled, Invicti finds and proves the issue.

Avoid verbose error messages

Detailed error messages can unintentionally leak stack traces, paths, or sensitive implementation details. Only return generic errors to clients and log full messages server-side.

Invicti identifies verbose responses and flags information disclosures during scans, helping you minimize leakages that could aid attackers.

Log and monitor API activity

Comprehensive logging and monitoring enable rapid detection of suspicious activity and support forensic analysis in case of a breach. Log access attempts, authentication failures, and unusual request patterns.

While logging implementation is outside the scope of vulnerability scanning, Invicti can help reduce attack opportunities that would otherwise go unnoticed without logging.

Best practices for API security testing

Manual security testing

Manual testing remains an important part of API security strategy. It allows experienced security professionals to spot logical flaws, misconfigurations, and business logic vulnerabilities that automated tools might miss. Code reviews, penetration tests, and red team exercises are especially useful for high-value or complex APIs.

However, manual testing alone is not scalable for modern environments where APIs are developed and updated rapidly. It should complement, not replace, automated testing.

Automated security testing

Automated API security testing enables continuous, scalable, and consistent protection. Dynamic application security testing (DAST) solutions like Invicti scan APIs in their running state to detect real, exploitable vulnerabilities, without needing access to source code to run the test.

Invicti automatically discovers API endpoints, maps their structure, and simulates attacks based on known techniques. Proof-based scanning technology enables Invicti validate many common vulnerabilities with safe, non-intrusive proof of exploit, reducing false positives and accelerating remediation.

Shift-left security for DevOps

Integrating security early in the software development lifecycle reduces cost and complexity. Developers can address issues before code reaches production.

Invicti supports shift-left strategies with scan configurations tailored to pre-production environments and integrations that deliver actionable results to development teams.

API scanning in CI/CD pipelines

APIs evolve quickly, often pushed to production multiple times per day. Integrating Invicti into CI/CD pipelines ensures each release is scanned automatically, with clear, verified results fed back into your workflow.

Invicti offers robust integrations with platforms like Jenkins, GitLab, Azure DevOps, and more—allowing you to automate API security testing across staging, QA, and production.

Turn API security best practices into real protection 

Following best practices for API security is essential, but best practices only work if they're continuously applied. Manual testing has its place, but automation is key to scalable, effective protection. Invicti’s dynamic scanning platform helps secure your APIs with real-time vulnerability detection, proof-based validation, and seamless integration into your development pipeline.

Secure your APIs from design to deployment—start scanning with Invicti today.

Frequently asked questions (FAQ) about API security best practices