BKDR_BREDOLAB.ZT
TrojanDownloader:Win32/Bredolab.AC (Microsoft); Backdoor.Win32.Bredolab.kaa (Kaspersky); Trojan-Downloader.Win32.Bredolab (GFI/Sunbelt); W32/Bredolab.KAA!tr.bdr (Fortinet); BDS/Bredolab.kaa (AntiVir)
Windows 2000, Windows XP, Windows Server 2003
Threat Type: Backdoor
Destructiveness: No
Encrypted: No
In the wild: Yes
OVERVIEW
This backdoor arrives as attachment to mass-mailed email messages. It may be dropped by other malware.
It connects to certain URLs. It may do this to remotely inform a malicious user of its installation. It may also do this to download possibly malicious files onto the computer, which puts the computer at a greater risk of infection by other threats. As of this writing, the said sites are inaccessible.
It opens a hidden Internet Explorer window.
TECHNICAL DETAILS
29,696 bytes
PE
UPX
Yes
17 Feb 2011
Downloads files
Arrival Details
This backdoor arrives as attachment to mass-mailed email messages.
It may be dropped by other malware.
Installation
This backdoor drops the following files:
- %User Profile%\Application Data\mdjaw.dat
(Note: %User Profile% is the current user's profile folder, which is usually C:\Windows\Profiles\{user name} on Windows 98 and ME, C:\WINNT\Profiles\{user name} on Windows NT, and C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003.)
Autostart Technique
This backdoor drops the following file(s) in the Windows User Startup folder to enable its automatic execution at every system startup:
- algzcu32.exe - copy of itself
Download Routine
This backdoor connects to the following malicious URLs:
- http://www.{BLOCKED}007.com/adm/controller.php?{random characters}
As of this writing, the said sites are inaccessible.
Other Details
This backdoor opens a hidden Internet Explorer window.
SOLUTION
8.900
7.842.03
17 Feb 2011
Step 1
For Windows XP and Windows Server 2003 users, before doing any scans, please make sure you disable System Restore to allow full scanning of your computer.
Step 2
Terminate a malware/grayware process
*Note: If the detected process is not displayed in theWindows Task Manager, continue doing the next steps.
- iexplore.exe
Step 3
Search and delete this file
- %User Profile%\Application Data\mdjaw.dat
Step 4
Scan your computer with your Trend Micro product to delete files detected as BKDR_BREDOLAB.ZT. If the detected files have already been cleaned, deleted, or quarantined by your Trend Micro product, no further step is required. You may opt to simply delete the quarantined files. Please check this Knowledge Base page for more information.
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