BKDR_XTRAT.JS

This backdoor arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

It executes then deletes itself afterward.

However, as of this writing, the said sites are inaccessible.

It steals system information. It logs a user's keystrokes to steal information.

Arrival Details

This backdoor arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

Installation

This backdoor executes then deletes itself afterward.

It injects itself into the following processes as part of its memory residency routine:

• iexplorer.exe
• svchost.exe

Other System Modifications

This backdoor adds the following registry entries:

HKEY_CURRENT_USER\Software\XtremeRAT
Mutex = "fdgdfgdfg"

HKEY_CURRENT_USER\Software\fdgdfgdfg
ServerStarted = "{Date and Time}"

Backdoor Routine

This backdoor opens the following port(s) where it listens for remote commands:

• TCP port 8888

It connects to the following URL(s) to send and receive commands from a remote malicious user:

• http://{BLOCKED}d.{BLOCKED}o.org:50002/1411.functions
• http://{BLOCKED}a.{BLOCKED}e.nu:50002/1411.functions

However, as of this writing, the said sites are inaccessible.

Download Routine

This backdoor connects to the following URL(s) to download its component file(s):

• http://www.{BLOCKED}ad.{BLOCKED}supdate.com/msdownload/update/v3/static/trustedr/en/authrootseq.txt

Information Theft

This backdoor steals system information.

It logs a user's keystrokes to steal information.

Stolen Information

The stolen information is saved in the following file:

• %Application Data%\Microsoft\Windows\fdgdfgdfg.dat

(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Windows\Profiles\{user name}\Application Data on Windows 98 and ME, C:\WINNT\Profiles\{user name}\Application Data on Windows NT, and C:\Documents and Settings\{user name}\Local Settings\Application Data on Windows 2000, XP, and Server 2003.)