There are currently not many sources in English about this event. There are multiple German articles coming out about this right now: https://www.heise.de/news

There are currently not many sources in English about this event. There are multiple German articles coming out about this right now: https://www.heise.de/news/Cyberattacke-auf-Berliner-Verwaltung-Ermittlungen-laufen-11416539.html https://www.heise.de/news/Cyberattacke-auf-Berliner-Verwaltu... https://www.tagesspiegel.de/berlin/wir-sind-praktisch-arbeitsunfahig-hackerangriff-auf-berliner-senatsverwaltungen--daten-abgeflossen-15952358.html https://www.tagesspiegel.de/berlin/wir-sind-praktisch-arbeit... Multiple people on the r/berlin subreddit are saying they can not apply for voting by post for the next election, on the 20th of september.