API Security Best Practices
API security best practices for authentication, object authorization, input validation, webhooks, abuse controls, monitoring, and continuous testing.
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Web Security Guides
Application-layer guidance for securing APIs, stopping automated abuse, and controlling resource consumption.
What these guides cover
Web security protects application entry points, APIs, identities, data, and constrained resources from unauthorized access and abuse. Valid syntax is not proof of a safe request: an authenticated caller can target another tenant's object, a bot can automate a legitimate checkout flow, and a distributed client can exhaust an expensive operation without crossing a simple per-IP threshold. Effective protection combines strict authentication and object-level authorization with input validation, resource-aware limits, automation detection, observable decisions, and controls close to the application logic that understands the requested operation and its business impact. Controls should degrade predictably when shared security dependencies are slow or unavailable.
Risks
- Broken object and function-level authorization
- Malicious input and unsafe downstream requests
- Credential stuffing, scraping, spam, and fraud
- Resource exhaustion and distributed automation
Control priorities
- Strong identity and authorization for every object and action
- Schema validation and constrained downstream behavior
- Identity-aware rate limits and bot detection
- Security telemetry, dry-run rollout, and incident response
Recommended reading order
Begin with API security best practices for the complete control baseline. Read the API abuse guide to understand valid-looking malicious automation, then use the rate limiting guide to select algorithms, identifiers, and failure behavior for resource controls.
Guides in this collection
What Is API Abuse? How Bots Exploit APIs
API abuse explained: how bots automate valid operations for fraud, scraping, account takeover, and cost exhaustion, and how application controls stop them.
Read guideRate Limiting Algorithms: Token Bucket vs Sliding Window vs Fixed Window
Compare token bucket, sliding window, fixed window, and leaky bucket rate limits by fairness, burst handling, state cost, and distributed API trade-offs.
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