A pretty simple suggestion

Well that's actually a good suggesion, also i have an idea, since the forum have a lot of shares with attachments, why don't you create a system that scans via api of virustotal once and after the results it's done taking the detection if it's greater than zero then next to the item or post shown a number and a virus or something as icon, if it's not and equals to zero then a green tick will appear there, also that might can give extra points to the user if it's clean, if it's not then no poiints (credits) would given. This can be done by programming an javascript/php parser and taking the information from uploaded file from it's hashes or may upload in time uploads the attachment into virus total (this requires more time load) but it's a verification, when upload finished the post is directly going normaly to be shared and a queue icon will shown until an async function check it's number of detection results. Well that's my suggesion i don't know if you get what i said, i hope that you do. That's just an idea. Sorry for my bad English.