Malware
Nymaim
aka nymain
Nymaim is a trojan downloader. It downloads (and runs) other malware on affected systems and was one of the primary malware families hosted on Avalanche.
Nymaim, also known as nymain, is a Windows malware family.
Background
Nymaim is a trojan downloader that fetches and runs additional malware on infected hosts, and it ranked among the main families served from the Avalanche platform. What sets it apart is that it shows a localized lockscreen while pulling down further payloads. It typically arrives via exploit kits and malvertising.
Source: Malpedia (Fraunhofer FKIE).