One of the wonderful and terrible things about the internet is how it allows people seeking others with hard-to-find traits to find them: advertisers can find people thinking about buying a refrigerator; people who think they might be trans can find others in the same boat and make common cause; people with the same rare disease can form support groups, and Nazis can find sociopaths to march through the streets of Charlottesville carrying tiki torches and chanting "Jews will not replace us." This has been especially pronounced in human sexuality.
Anonymous access to porn lets people explore different sexual activities.
Online dating services lets people find those who share their kinks, interests, or special needs.
Enter 3fun, an online dating service for those seeking group sex with others.
Pen Test Partners notified 3fun of the defect on July 1, but it was not remediated for "weeks." In its report, Pen Test Partners notes that it has only scratched the surface of the defects in 3fun's security, and speculates that there could be more (and even graver) defects in the system.