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Global Accelerated Learning • Est. 1999
Glossary Term Input Validation

Training Camp • Cybersecurity Glossary

What is Input Validation?

Input validation verifies incoming data against expected type, length, and format, ideally server-side with allowlists, to prevent injection attacks.

Glossary > Application & API Security > Input Validation

Understanding Input Validation

Input validation is the security practice of verifying that data entering an application conforms to expected type, length, format, and range before it is processed. Allowlist or positive validation, which accepts only known-good values, is preferred over denylist filtering, and validation should be enforced on the server side because client-side checks can be bypassed. Robust input validation is a primary defense against injection attacks such as SQL injection, cross-site scripting, and command injection.

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