Blue Is the New Black (Market): Privacy Leaks and Re-Victimization from Police-Auctioned Cellphones.

In the United States, items in police possession are often sold at auction if they are not claimed. This includes cellphones that the police obtained through civil asset forfeiture, that were stolen, or that were turned in to lost-and-found. Thousands of US police departments partner with a website, PropertyRoom, to auction their items. Over the course of several months, we purchased 228 cellphones from PropertyRoom to ascertain whether they contained personal information. Our results show that a shocking amount of sensitive, personal information is easily accessible, even to a "low-effort" adversary with no forensics expertise: 21.5% of the phones we purchased were not locked at all, another 4.8% used top-40 most common PINs and patterns, and one phone had a sticky-note from the police with the PIN on it. We analyze the content on the 61 phones we could access, finding sensitive information about not only the phones' previous owners, but also about their personal contacts, and in some cases, about victims of those persons' crimes. Additionally, we analyze approximately two years of PropertyRoom cellphone auctions, finding multiple instances of identifying information in photos of the items being auctioned, including sticky-notes with PINs, owners' names and phone numbers, and evidence stickers that reveal how the phones were obtained and the names of the officers who obtained them. Our work shows that police procedures and phone auctions can be a significant source of personal information leakage and re-victimization. We hope that our work is a call to arms to enforce new policies that either prohibit the selling of computing devices containing user information, or at the very least impose requirements to wipe phones in a manner that the US federal government already employs.