Symfony is a PHP framework for web and console applications and a set of reusable PHP components. Prior to versions 5.4.54, 6.4.46, 7.4.19, and 8.1.7, HeaderUtils::split() parsed header values with a pattern whose token alternative also matched whitespace, followed by a (?
Inefficient Regular Expression Complexity The product uses a regular expression with a worst-case computational complexity that is inefficient and possibly exponential.