Accepted or Rejected? — TechKnowSurge

About this interactive

Many web applications take input in forms and pass it to a database in SQL commands. If a user can put code into a field, the database may read it as part of the command, so an attacker can log in without a password or add, change, delete or pull out data. That is SQL injection, one of several kinds of injection attack. The defence is input validation: every field gets rules, and anything outside them is refused before it reaches the database. The lesson lists data type checks (letters only, numbers only), ranges, formats (a phone number or ZIP code), length limits, required fields, uniqueness checks against duplicate records, consistency checks between fields (a ship date not before the order date) and a code check, so nothing that resembles code gets in. Strict rules have a cost: a letters-only name field refuses O'Brien. Real forms handle that with parameterized queries behind the form, so a quote mark is safe as data; the rules here are the lesson's.

What you'll learn

Apply a field's validation rule (type, length, format, range, consistency or code check) to decide whether an input is accepted or rejected
Explain how validating every input stops injection, where input such as quote marks and SQL words is read as part of a database command

Aligned to

CompTIA Security+

4.1 Given a scenario, apply common security techniques to computing resources.

Key terms

Input Validation: The process of enforcing rules on user-supplied data to ensure it conforms to expected type, length, format, and content before it is processed by an application.
SQL Injection: An attack that inserts malicious SQL code into a query to manipulate a database.
Vulnerability: A weakness in a system, application, or process that can be exploited by a threat actor.

Topics

Interactive Streak Sort

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