view_component is a framework for building reusable, testable, and encapsulated view components in Ruby on Rails. Versions prior to 3.9.0 and 2.83.0 have a cross-site scripting vulnerability that has the potential to impact anyone rendering a component directly from a controller with the view_component gem. Note that only components that define a "#call" method (i.e. instead of using a sidecar template) are affected. The return value of the "#call" method is not sanitized and can include user-defined content. In addition, the return value of the "#output_postamble" methodis not sanitized, which can also lead to cross-site scripting issues. Versions 3.9.0 and 2.83.0 have been released and fully mitigate both the "#call" and the "#output_postamble" vulnerabilities. As a workaround, sanitize the return value of "#call".