Trojan-Downloader:JS/Advedo

Classification

Malware

Trojan-Downloader

JS

JS/Advedo

Summary

This type of trojan secretly downloads malicious files from a remote server, then installs and executes the files.

Removal

Automatic action

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.

Suspect a file is incorrectly detected (a False Positive)?

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 detection database 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.

Find out more

Knowledge Base

Find the latest advice in our Community Knowledge Base.

User Guide

See the user guide for your product on the Help Center.

Contact Support

Chat with or call an expert for help.

Submit a sample

Submit a file or URL for further analysis.

Technical Details

Trojan-Downloader:JS/Advedo is part of a multi-stage malware that is injected into legitimate websites. When a visitor arrives at the compromised website, the malware uses several scripts to force a file download onto the visitor's computer.

The various scripts used are written in JScript and VBS.

Activity

The first part of this script Trojan is injected into a legitimate website and placed after the website's closing HTML tag. This script allows the execution of another script from the following predetermined website:

  • https://qzh.txshi.com/

The second part of the malware inserts an iframe into the website. The site inserted is still contained from the same domain.

The third part of the malware (a combination of JScript and VBS) downloads a file from the following website:

  • https://qzh1.txshi.com/

At the time of analysis, the downloaded file is no longer available.

If the download is successful, the file is saved into the temporary folder of the system as:

  • nettool.exe

The file ~net.bat is then created in the temporary folder and is used to execute the downloaded file.