Trojan.Nymaim
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Short bio
Trojan.Nymaim is Malwarebytes’ detection name for a family of Trojan downloaders that also use a screen locker to demand a ransom.
Malicious behavior
Trojan.Nymaim is a Trojan downloader. These downloaders are Trojans that download (and run) other malware on affected systems. Trojan.Nymaim is different in that it displays a localized lockscreen while it downloads additional malware. Trojan.Nymaim is usually delivered by exploit kits and malvertising.
Protection
Malwarebytes blocks Trojan.Nymaim
Home remediation
You can use the Malwarebytes Anti-Malware Nebula console to scan endpoints.
Nebula endpoint tasks menu
Choose the Scan + Quarantine option. Afterwards you can check the Detections page to see which threats were found.
On the Quarantine page you can see which threats were quarantined and restore them if necessary.