Computer Science Student Shows Venmo Transactions Can Be Easily Acquired

A year after a privacy researcher showed the world that Venmo transactions could be easily accessed, a computer science student scraped seven million Venmo transactions to increase awareness of the issue.

• By Kaitlyn DeHaven
• Jun 19, 2019

A computer science student, Dan Salmon, has been scraping Venmo transactions for the past six months to prove that Venmo’s public activity is not hard to obtain, even after last year, when a privacy researcher showed that Venmo need to curb its privacy issue. The result is that seven million Venmo transactions were obtained by Salmon in this six-month period.

Salmon told TechCrunch he did this in order to raise awareness and encourage users to set their transactions to private. He said that despite Venmo changing their privacy policy, it is still easy to gain access to millions of transactions through Venmo’s developer API. User permission is not necessary to access this information.

“There’s truly no reason to have this API open to unauthenticated requests,” he told TechCrunch. “The API only exists to provide like a scrolling feed of public transactions for the home page of the app, but if that’s your goal, then you should require a token with each request to verify that the user is logged in.”

Sam Bakken, the senior product marketing manager at OneSpan, said that Venmo purposefully designed the homepage news feed feature in order to increase engagement, and some users enjoy looking through the feed to see what their friends are doing. This means that some users leave their transactions available to the public on purpose. He said that he hopes this information will encourage some users to go private with their information.

“Users do have the ability to decide whether their transactions are shared publicly or with friends or not at all,” Bakken said. “I’d argue Venmo should default to keeping users’ transactions private, and if this incident doesn’t convince Venmo to change their policy – I hope at least more people will become aware of this and consider changing their settings.”

Ameya Talwalkar, co-founder and CPO of Cequence Security, said that scraping attacks are becoming increasingly harder to prevent due to the hyper-connectivity culture of this age.

“Many of today’s hyper-connected organizations are faced with the challenge of how to address content scraping attacks in an efficient and scalable manner,” Talwalkar said. “The impact of this attack can be wide-ranging, starting from overspending on infrastructure to devastating loss of intellectual property. Of all the automated business logic abuse attacks, content scraping is the most difficult to prevent.”