Caution Telegram: Data on group members and chat content can easily be tapped

 An unnamed data miner has now shown how easy it is to obtain personal and chat data from the advertised "secure messenger" Telegram.

The Twitter user Datenliebe is data mining on Telegram. He is trying to extract as much personal and conversation data from the service as possible. According to the Twitter feed, the user's activity seems to be concentrated mainly in the camp of Corona critics.

Most recently, Datenliebe had reached out to T-Online editors to offer his insights. The "data hunter" - as T-Online calls him - also claims to have already provided information to the BBC. T-Online does not know the user. The contact was via the messenger Threema.

Telegram groups easy to read

What Datenliebe has to tell may scare a large number of Telegram users - namely all those who are active in public and closed groups and feel their identity is protected there. After all, Telegram itself always emphasizes that it is a secure messenger.

In fact, this is only true for messaging outside of groups, i.e. in individual chats, and there only when a so-called "secret chat" is started. Only in this case, the chat is encrypted end-to-end and cannot be accessed from the outside.

In groups, things look different, as Datenliebe shows. Intelligence agencies and other security services would have an easy time extracting and storing data from Telegram groups.

He himself has been "collecting content in a database for years". The public groups in particular are easy to read, because you don't even have to be a member there. Closed groups have to be joined.

This is likely to prove somewhat difficult for groups with clearly criminal content. However, when it comes to the groups created as a result of the fight against conspiracy narrators in the Coronaum field, for example, "joining" such a group is not much more than a tap on the corresponding button. It is precisely this group of people that likes to gather on Telegram because the messenger - unlike Youtube, Twitter or Facebook, for example - is not a platform that is subject to the provisions of the Network Enforcement Act.

According to Datenliebe, once access to the desired group has been granted, Telegram's own extensive interface can even be accessed to facilitate the data mining work, making it particularly easy to store and collect data.

Identifying phone numbers of group members

In this way, the telephone numbers of the group members can also be obtained. This in turn can be used to find out in which groups a telephone number is stored, i.e. where a person is active everywhere. The unique identification by phone number can then be used to create profiles. According to Datenliebe, the contents of group chats can still be read out and assigned years later.

Those who switched to Telegram because of the new Whatsapp terms and conditions should probably reconsider their decision.