Symfony 1 is a community-driven fork of the 1.x branch of Symfony, a PHP framework for web projects. Starting in version 1.1.0 and prior to version 1.5.19, Symfony 1 has a gadget chain due to dangerous deserialization in `sfNamespacedParameterHolder` class that would enable an attacker to get remote code execution if a developer deserializes user input in their project. Version 1.5.19 contains a patch for the issue.

Gadget chain in Symfony 1 due to uncontrolled unserialized input in sfNamespacedParameterHolder