SoK: Self-Generated Nudes over Private Chats: How can Technology Contribute to a Safer Sexting?

More and more people take advantage of mobile apps to strike up relationships and casual contacts. This sometimes results in the sharing of self-generated nudes. While this opens a way for sexual exploration, it also raises concerns. In this paper, we review existing technology-assisted permissive proposals/features that provide security, privacy or accountability benefits when sharing nudes online. To do so, we performed a systematic literature review combing through 10,026 search results and cross-references, and we identified real-world solutions by surveying OS features and 52 dating, messaging and social network apps. We systematized knowledge by defining a sexting threat model, deriving a taxonomy of the proposals/features, discussing some of their shortcomings, organizing privacy-related concepts, and providing take-aways with some directions for future research and development. Our study found a very diverse ecosystem of academic proposals and app features, showing that safer sexting goes far beyond nude detection. None of the techniques represents the ultimate solution for all threats, but each contributes to a safer sexting in a different way.