What it is
API security protects the way applications communicate through endpoints, tokens, and data exchanges. APIs expose login flows, data retrieval, and account operations, making them attractive targets. Weak authentication, missing rate limits, leaked API keys, unvalidated input, or overly permissive actions let attackers abuse business logic. As organisations connect more SaaS tools and cloud services, their API footprint extends far beyond the traditional perimeter.
Why it matters
APIs are now one of the most abused attack surfaces. Adversaries bypass web front-ends by calling APIs directly, siphoning data, automating credential stuffing, or tampering with workflows. Because machine-to-machine traffic can look routine, malicious behaviour often goes unnoticed without intentional safeguards.
How to reduce risk
- Enforce strong authentication (OAuth, signed tokens, regular key rotation).
- Apply strict rate limiting and bot detection to throttle abuse.
- Validate every input and response with defined schemas.
- Encrypt traffic with HTTPS/TLS and monitor for downgrade attempts.
- Keep sensitive internal APIs off the public internet or behind zero-trust brokers.