CyberGuard dictionary / Web Application Security
API Security
API security protects application interfaces, their data, and operations from unauthorized use and abuse.
In simple terms
An API needs checks on who is calling, what each caller may do, and whether requests and responses expose too much.
Technical explanation
Controls include authentication, object and function authorization, input validation, resource limits, secret handling, inventory, and logging. Each endpoint needs server-side enforcement; a hidden button or client-side check does not protect it.
An API exposes data and actions directly to clients, so each endpoint must validate identity, authorization, input, and resource use. Inventory and logs help find forgotten versions and abusive patterns.
Examples in practice
A customer API checks that the signed-in customer owns an invoice before returning it, even when the invoice identifier is valid.
A mobile client requests an invoice with a valid ID from another account. The API checks tenant ownership, rejects the request, and logs the attempt without returning invoice details.
Why it matters
APIs often expose sensitive business functions directly, making missing checks consequential.
VERIFY & LEARN MORE
Sources and further reading
Published 2026-10-15 · Last updated 2026-10-15 · CyberGuard editorial content. Source links provide context; they do not imply endorsement.