Malware type: JavaScript

Aliases: Trojan-Downloader.JS.Inor.a (Kaspersky), JS/Wonka (McAfee), Downloader (Symantec), TR/Dldr.Inor.A.18 (Avira), Mal/ObfJS-H (Sophos),

In the wild: No

Language: English

Overall risk rating:

Reported infections:

Damage potential:


Distribution potential:



A JavaScript may be written with malicious intent. Script malware makes use of Microsoft's Windows Scripting Host (WSH). WSH is a Windows administration tool that makes objects and services available for various scripts and provides a set of guidelines within which the script is executed. It allows remote malicious users to run scripts from the Windows desktop, Windows Explorer, and Windows command prompt.

WSH cannot distinguish between malicious and non-malicious script. Double-clicking on a script malware file will cause the malware to run its main action and payload, thus infecting the system.

For additional information about this threat, see:


Pattern file needed: 4.507.00

Pattern release date: Jun 3, 2007


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