Online platform Reporter.lu published the allegations with backing from IT experts.
Third parties are said to easily be able to access names of those using Digicash, and can assign mobile numbers to these names. Hackers can therefore misuse personal data of those using the app.
The "Chaos Computer Club Lëtzebuerg" described it as a semi-public database. The issue is that hackers can put any phone number into the app, and if the number's owner has used Digicash before, then hackers can access their personal data. Such information could then be sold on to less scrupulous criminals.
Reporter.lu queried the issue with Digicash and were told it was part of the system and that no money would be transferred to the wrong person.
The app works in tandem with five Luxembourgish banks. Clients are apparently kept informed over the use of their data.