ATTENTION
As of today, a new blackmail Trojan "Petya" seems to be on the loose. In addition to attack targets in Russia and Ukraine, Western European companies now also seem to be affected.
Similar to the WannaCry attack in May, a vulnerability in Windows file shares is being exploited.
You can also find more detailed information at
https://www.heise.de/security/meldung/Rueckkehr-von-Petya-Kryptotrojaner-legt-weltweit-Firmen-und-Behoerden-lahm-3757047.html