symfony/validator is a module for the Symphony PHP framework which provides tools to validate values. It is possible to trick a `Validator` configured with a regular expression using the `$` metacharacters, with an input ending with `\n`. Symfony as of versions 5.4.43, 6.4.11, and 7.1.4 now uses the `D` regex modifier to match the entire input. Users are advised to upgrade. There are no known workarounds for this vulnerability.