Sanitize $_REQUEST, $_POST and $_GET before the processing of TYPO3 in backend or frontend starts. Take a look into the documentation how to add your own rules or see which one exist.
11 LTS 12 LTS
4.5 LTS 6.2 LTS 7 LTS 8 LTS 9 LTS 10 LTS 11 LTS 12 LTS
Released version 12.0.3. Check changelog in documentation on github for more information.
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