Trojan-Downloader.JS.Agent.ftu

Technical Details

This program has a malicious payload. It is an HTML document containing Java Script. It is 43 256 bytes in size.

Payload

Once launched, the Trojan uses additional JS scripts to strip obfuscations from its main malicious code. The Trojan then determines the operating system version, the current browser and the plugins installed in browser. It exploits a vulnerability in Java Deployment Toolkit (JDT) that arises due to incorrect processing of URL. This allows the malicious user to send random parameters to Java Web Start (JWS) (CVE-2010-0886). The malicious user generates a specially crafted link and sends it as the parameter of vulnerable "launch()" function. This way the Trojan downloads and launches the malicious file for execution from the following link:

\\76.***.98\pub\new.avi

It also sends a link for downloading:

http://shr***sht.co.cc/d.php?f=95&e=1

The Trojan uses ActiveX objects with unique identifiers to run its malicious script in MS Internet Explorer:

{CAFEEFAC-DEC7-0000-0000-ABCDEFFEDCBA}
{8AD9C840-044E-11D1-B3E9-00805F499D93}
{CA8A9780-280D-11CF-A24D-444553540000}

To execute its script in Mozilla Firefox and other NPAPI browsers, the Trojan determines the following MIME types:

application/npruntime-scriptable-plugin;deploymenttoolkit
application/java-deployment-toolkit
application/vnd.adobe.pdfxml
application/vnd.adobe.x-mars

The malware then determines the plugins installed in the browser and Adobe Reader and Adobe Acrobat ActiveX objects. Then, depending on the PDF Reader version, in a hidden frame it downloads a PDF exploit from one of the following links:

http://<domain_name_of_infected_server>/games/pdf.php?f=95
http://<domain_name_of_infected_server>/games/pdf2.php?f=95

At the time of writing, these links were inactive.

Removal instructions

If your computer does not have antivirus protection and has been infected by this malicious program, follow the instructions below to delete it:

1. Delete the original Trojan file (its location will depend on how the program originally penetrated the infected computer).
2. Empty the Temporary Internet Files directory, which contains infected files (see How to delete infected files from Temporary Internet Files folder?):

   %Temporary Internet Files%

3. Update Sun Java JRE and JDK to the latest versions.
4. Empty the current user's temporary files directory:

   %Temp %\