Malware
Troldesh
aka Shade
According to Malwarebyte, Ransomware is a type of malware that prevents users from accessing their system or personal files and demands ransom payment in order to regain access.
Troldesh, also known as Shade, is a Windows malware family.
Background
Malwarebytes notes that ransomware is malware that blocks victims from reaching their systems or personal files and then demands payment to restore access. Ransom.Troldesh propagates through malspam, usually carried in attached .zip files, and at times relies on a CMS running on a hacked website to host its downloads.
Source: Malpedia (Fraunhofer FKIE).