Yes, look at Amazon Rekognition. I use it (very successfully) for a website that used to encounter similar issues with file upload abuse. In my case, image upl

Yes, look at Amazon Rekognition. I use it (very successfully) for a website that used to encounter similar issues with file upload abuse. In my case, image uploads aren't mandatory for users, but they are very helpful in identifying the spammers (for some reason, the spammers almost always try to upload images that get filtered, so it makes it easier to spot them). That, combined with an IP check (getipintel.net) has almost completely eliminated the spam issues on my site.