Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.

CGI versions before 5.00 for Perl allow the POSTDATA, PUTDATA, PATCHDATA and XForms:Model parameters to be set from the query string or form fields.

CGI stores a non-form request body under POSTDATA, PUTDATA or PATCHDATA, and an XForms body under XForms:Model, but also accepts these names from the query string, a form field or a multipart part, so an application cannot tell a client-sent value from the real body.

A cross-site HTML form can post POSTDATA={"admin":true} to an endpoint that reads JSON from param('POSTDATA'), a request forgery that needs no CORS preflight.