We're gradually updating threat actor names in our reports to align with the new weather-themed taxonomy. Learn about Microsoft threat actor names
JS/Nemucod
Aliases: Trojan-Downloader.JS.Agent.hdm (Kaspersky) JS/Downloader (McAfee) Troj/JSDldr-AT (Sophos) JS.Downloader (Symantec)
Summary
Windows Defender detects and removes this threat.
This family of threats are .zip attachments that, when opened, try to download and install other malware on your PC, including ransomware and information stealing malware, such as:
- Crowti, Tescrypt, and Locky, which encrypt your files and demand payment to decrypt them
- Fareit, which attempts to steal your passwords and personal information
- Ursnif, which records information about you and your PC
The trend towards increasingly sophisticated malware behavior, highlighted by the use of exploits and other attack vectors, makes older platforms so much more susceptible to ransomware attacks. From June to November 2017, Windows 7 devices were 3.4 times more likely to encounter ransomware compared to Windows 10 devices.
Read our latest report: A worthy upgrade: Next-gen security on Windows 10 proves resilient against ransomware outbreaks in 2017.
This threat might install ransomware. See our ransomware page for more information.
Use the following free Microsoft software to detect and remove this threat:
- Windows Defender for Windows 10 and Windows 8.1, or Microsoft Security Essentials for Windows 7 and Windows Vista
- Microsoft Safety Scanner
- Microsoft Windows Malicious Software Removal Tool
You should also run a full scan. A full scan might find hidden malware.
Advanced troubleshooting
To restore your PC, you might need to download and run Windows Defender Offline. See our advanced troubleshooting page for more help.
Get more help
You can also visit our advanced troubleshooting page or search the Microsoft virus and malware community for more help.
If you’re using Windows XP, see our Windows XP end of support page.
