Anyone can track a Venmo user’s purchase history and glean a detailed profile – including their drug deals, eating habits and arguments – because the payment app lacks default privacy protections.
This was the finding of a Berlin-based researcher, Hang Do Thi Duc, who analysed the more than 200 million public Venmo transactions made in 2017. Her aim was to highlight the privacy risk from using a seemingly innocuous peer-to-peer app.
By accessing the data through a public application programming interface, Do Thi Duc was able to see the names of every user who hadn’t changed their settings to private, along with the dates of every transaction and the message sent with the payment. This allowed her to explore the lives of unsuspecting Venmo users and learn “an alarming amount about them”.
The default state for transactions when a user signs up to the app is “public”, which means they can be seen by anyone on the internet. Users can change this to “private” by navigating to the app’s settings, but it’s not clearly highlighted during sign-up.