Trojan-Downloader:W97M/Downloader

Classification

Category :

Malware

Type :

Trojan-Downloader

Platform :

W97M

Aliases :

W97m.downloader, W97m.downloader.[variant]

Summary

Variants in the Trojan-Downloader:W97M/Downloader family are specially-crafted Microsoft Word document files that, when opened, silently execute a malicious macro embedded in the file. The macro will typically connect to a remote server and download additional files to the affected machine.

Removal

Based on the settings of your F-Secure security product, it will either move the file to the quarantine where it cannot spread or cause harm, or remove it.

A False Positive is when a file is incorrectly detected as harmful, usually because its code or behavior resembles known harmful programs. A False Positive will usually be fixed in a subsequent database update without any action needed on your part. If you wish, you may also:

  • Check for the latest database updates

    First check if your F-Secure security program is using the latest updates, then try scanning the file again.

  • Submit a sample

    After checking, if you still believe the file is incorrectly detected, you can submit a sample of it for re-analysis.

    Note: If the file was moved to quarantine, you need to collect the file from quarantine before you can submit it.

  • Exclude a file from further scanning

    If you are certain that the file is safe and want to continue using it, you can exclude it from further scanning by the F-Secure security product.

    Note: You need administrative rights to change the settings.

Technical Details

The detection 'W97M.Downloader.[variant]' identifies malicious macro code embedded in a Microsoft Word document file. This file is usually distributed as an attachment to an email message.

The 'bait' Word document file will typically be crafted to look legitimate and appealing to a user (for example, pretending to be a resume or containing interesting news items or content), so that they are drawn into opening the file.

Once the file is opened, the malicious macro code embedded in the file is launched. Typically, the macro's malicious actions will silently take place in the background, evading the user's notice.

The specific malicious actions performed by the macro will differ by variant, but usually involve downloading and installing additional malicious files onto the affected machine. For an example of a Downloader variant and its behavior, see: