“Ethical issues in research using datasets of illicit origin” by Daniel R. Thomas, Sergio Pastrana, Alice Hutchings , Richard Clayton and Alastair R. Beresford
▻https://dl.acm.org/citation.cfm?id=3131389 (PDF in ▻https://www.cl.cam.ac.uk/~drt24/papers/2017-ethical-issues.pdf or on Sci-Hub)
It is mostly about leaked datasets (such as the #Patreon database) but it talks also about active network measurements (such as the #Carna_scan). Very good reading around the question “crackers breached an Internet server, distribute the database they got, can I use it for honest research?”