GM Grimmi has recently published an announcement about webifying Jump Freighters to prevent them from cancelling warp and docking. Broken code in the game disallows cancelling warp when webified, and players used it to some extent in low sec to catch and kill Jump Freighters at stations, effectively denying them ability to dock back to safety. This is now considered an exploit and perma-bannable offense.
Webifying freighters to make them warp faster is not an exploit though! Many players voiced their concerns that using an alt to web a Freighter is bannable too, but this is fortunately not true.
It is also worth mentioning, that pilots who lost their Jump Freighters in this manner are likely eligible for a reimbursement.