Escape and sanitize input and output?

Tagged escape, input, output, sanitize  Languages 

Thinking about escaping and sanitizing input and output? Read this: https://security.stackexchange.com/questions/95325/input-sanitization-vs-output-sanitization

Rules:

  • Always sanitize output

By sanitizing the output, you can fix issues caused by bugs in the input sanitizer without touching the database.

  • Sanitize input, if it makes sense:

For example, if there’s a risk that input becomes invalid after sanitization then it’s better to store the data raw.

This is also a good idea, if there are multiple output formats and sanitizing the input might break something.