A massive ransomware campaign targeting QNAP devices worldwide is underway, and users are finding their files now stored in password-protected 7zip archives. A bug was discovered last night that allowed victims to recover their 7zip password for free but was fixed soon after being discovered. The attackers use 7-zip to move files on QNap devices into encrypted archives. To extract these archives, victims will need to pay 0.01 Bitcoins, which is approximately $557.74, to get a password for their archived files.
Source: https://www.bleepingcomputer.com/news/security/massive-qlocker-ransomware-attack-uses-7zip-to-encrypt-qnap-devices/