Joel Samper (Sam) was awarded the MaxData Informatic Excellence award for his PhD research, during the Ciências ULisboa 115th anniversary ceremony, which investigates technological approaches for safer image sharing in messaging apps in general, and nudes in particular. His work aims to expand the potential of technologies for having more privacy over intimate images, i.e., having agency to share in a more controlled way.

Sam started his PhD in 2022 with a “la Caixa” Foundation fellowship and he is currently sponsored by an FCT studentship. He has published two papers on the subject and is working already on a third project.

• SoK: Self-Generated Nudes over Private Chats: How Can Technology Contribute to a Safer Sexting? Presented at SP 2025, building a sexting threat model from prior studies, and a classification of safer-sexting technologies from a systematic literature review and an empirical survey of app features.

• Leveraging Remote Attestation APIs for Secure Image Sharing in Messaging Apps Presented at EDCC 2025, analyzing the properties, building a prototype and running experiments, on an architecture that uses remote attestation to safeguard the security of messaging features such as the view-once images.

• He is currently working on a cryptographic protocol and a digital watermarking algorithm that integrate seamlessly to trace the identity of who originated a non-consensual disclosure of an intimate image, which would allow to present undeniable forensic evidence in court.