GHSA-MQF3-QPC3-G26Q Silverstripe Framework has a Reflected Cross Site Scripting (XSS) in error message

!IMPORTANT This vulnerability only affects sites which are in the "dev" environment mode. If your production website is in "dev" mode, it has been misconfigured, and you should immediately swap it to "live" mode. See https://docs.silverstripe.org/en/developerguides/debugging/environmenttypes/ for...