Graduate student Dan Salmon has released online seven million Venmo transfers, scraped from the social payment biz in recent months, to call attention to the privacy risks of public transaction data.
Venmo, for the uninitiated, is an app that allows friends to pay each other money for stuff. El Reg‘s Bay Area vultures primarily use it for settling restaurant and bar bills that we have no hope of expensing; one person pays on their personal credit card, and their pals transfer their share via Venmo. It makes picking up the check a lot easier.
Because it’s the 2010s, by default, Venmo makes those transactions public along with attached messages and emojis, sorta like Twitter but for payments, allowing people to pry into strangers’ spending and interactions. Who went out with whom for drinks, who owed someone a sizable debt, who went on vacation, and so on.
“I am releasing this dataset in order to bring attention to Venmo users that all of this data is publicly available for anyone to grab without even an API key,” said Salmon in a post to GitHub. “There is some very valuable data here for any attacker conducting [open-source intelligence] research.”
Despite past criticism from privacy advocates and a settlement with the US Federal Trade Commission, Venmo has kept person-to-person purchases public by default.
Last July, Berlin-based researcher Hang Do Thi Duc explored some 200m Venmo transactions from 2017 and set up a website, PublicByDefault.fyi, to peruse the e-commerce data. His stated goal was to change people’s attitudes about sharing data unnecessarily.
When The Register asked about transaction privacy last year, after a developer created a bot that tweeted Venmo purchases mentioning drugs, a company spokesperson said, “Like on other social networks, Venmo users can choose what they want to share on the Venmo public feed. There are a number of different settings that users can customize when it comes to sharing payments on Venmo.”
The current message from the company is not much different: “Venmo was designed for sharing experiences with your friends in today’s social world, and the newsfeed has always been a big part of this,” a Venmo spokesperson told The Register in an email. “Our users trust us with their money and personal information, and we take this responsibility very seriously.”
“I think Venmo is resisting calls to make their data private because it would go against the entire pitch of the app,” said Salmon. “Venmo is designed to be a “‘social’ app and the more open and social you make things, the more you open yourself to problems.”