Twitter has misused data of users. This admitted the short message service. The company also used phone numbers and email addresses provided by users for security purposes, such as two-factor authentication, to advertise personalized ads.

This was a mistake, the company wrote. They have already been fixed on 17 September. Companies that advertise on Twitter can upload lists of their customers' contact details to the short message service in order to be able to specifically address them in the service. The e-mail addresses and telephone numbers deposited by the users for security purposes were aligned with these lists, although this should not have happened, explained Twitter. The advertisers would not have had access to this data. How many users were affected is unclear.

Facebook also had to admit a few months ago, having diverted personal data of users.