SQL injection

Input that changes the meaning of a database query because it was pasted into the SQL text instead of passed as a parameter.

If a query is built as text with the user’s input inside, a crafted value can close the string and add its own SQL: read other users’ data, bypass a login, delete tables. Parameterized queries and most ORMs send data separately from the query, which removes the problem. It still appears in raw queries, dynamic sorting and search filters.

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Related terms

OWASP Top 10: The OWASP Foundation’s list of the ten most critical web application security risks, updated every few years.
Runtime validation (Zod): Checking at run time that data from outside (requests, APIs, files, models) matches the type your code assumes.
RCE (remote code execution): A vulnerability that lets an attacker run their own code on your server or device over the network.

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