Unidentified hackers have spied on three German IT firms that provide services to federal ministries and agencies. According to the letter of caution, the first attack—on the Dortmund-based IT firm Adesso—became public knowledge. Adesso claims on its website that outside IT security experts discovered that the unidentified hackers had access to the corporate networks. Likewise based in Dortmund, Materna was impacted. It has not yet been feasible to establish whether email correspondence, particularly with federal authorities, has been lost, according to Materna. Init, a Berlin-based corporation, was a victim of the third attack. The Interior and Economics Ministries of the Federal Government are among its clients. At the request of BR, Init acknowledged the cyberattack. Customers who were impacted have been notified.

The Materna security breach also prevented Vodafone's prepaid cards from being registered online and prevented online sales from proceeding. Shortly after Materna acknowledged conducting a skillfully designed cyberattack on the company, the sale of SIM cards on Vodafone's website was suspended. In order to protect system security and client data, Vodafone temporarily disabled Materna's CallYa services. A statement claims that the business is once more up and running. Systems that were newly built or totally modified were used by employees; they were never connected to the compromised infrastructure.